uapi: add metadata flag to xdp flags #4

mswiatko · 2021-08-09T10:28:56Z

Add this flag to allow user to inform driver that metadata is used.
Set flag is sent to driver via exsisting ndo_bpf call in flag field.

Signed-off-by: Michal Swiatkowski michal.swiatkowski@intel.com

Second approach to inform driver about metadata. Let user decide if metadata should be supported or not. Add this flag to allow user to inform driver that metadata is used. Set flag is sent to driver via exsisting ndo_bpf call in flag field. Signed-off-by: Michal Swiatkowski <michal.swiatkowski@intel.com>

The ordering of MSI-X enable in hardware is dysfunctional: 1) MSI-X is disabled in the control register 2) Various setup functions 3) pci_msi_setup_msi_irqs() is invoked which ends up accessing the MSI-X table entries 4) MSI-X is enabled and masked in the control register with the comment that enabling is required for some hardware to access the MSI-X table Step #4 obviously contradicts #3. The history of this is an issue with the NIU hardware. When #4 was introduced the table access actually happened in msix_program_entries() which was invoked after enabling and masking MSI-X. This was changed in commit d71d643 ("PCI/MSI: Kill redundant call of irq_set_msi_desc() for MSI-X interrupts") which removed the table write from msix_program_entries(). Interestingly enough nobody noticed and either NIU still works or it did not get any testing with a kernel 3.19 or later. Nevertheless this is inconsistent and there is no reason why MSI-X can't be enabled and masked in the control register early on, i.e. move step #4 above to step #1. This preserves the NIU workaround and has no side effects on other hardware. Fixes: d71d643 ("PCI/MSI: Kill redundant call of irq_set_msi_desc() for MSI-X interrupts") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.344136412@linutronix.de

Fix crash on reboot on a system with ASIX AX88178 USB adapter attached to it: | asix 1-1.4:1.0 eth0: unregister 'asix' usb-ci_hdrc.0-1.4, ASIX AX88178 USB 2.0 Ethernet | 8<--- cut here --- | Unable to handle kernel NULL pointer dereference at virtual address 0000028 | pgd = 5ec93aee | [0000028] *pgd=00000000 | Internal error: Oops: 5 [#1] PREEMPT SMP ARM | Modules linked in: | CPU: 1 PID: 1 Comm: systemd-shutdow Not tainted 5.14.0-rc1-20210811-1 #4 | Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) | PC is at phy_disconnect+0x8/0x48 | LR is at ax88772_unbind+0x14/0x20 | [<80650d04>] (phy_disconnect) from [<80741aa4>] (ax88772_unbind+0x14/0x20) | [<80741aa4>] (ax88772_unbind) from [<8074e250>] (usbnet_disconnect+0x48/0xd8) | [<8074e250>] (usbnet_disconnect) from [<807655e0>] (usb_unbind_interface+0x78/0x25c) | [<807655e0>] (usb_unbind_interface) from [<805b03a0>] (__device_release_driver+0x154/0x20c) | [<805b03a0>] (__device_release_driver) from [<805b0478>] (device_release_driver+0x20/0x2c) | [<805b0478>] (device_release_driver) from [<805af944>] (bus_remove_device+0xcc/0xf8) | [<805af944>] (bus_remove_device) from [<805ab26c>] (device_del+0x178/0x4b0) | [<805ab26c>] (device_del) from [<807634a4>] (usb_disable_device+0xcc/0x178) | [<807634a4>] (usb_disable_device) from [<8075a060>] (usb_disconnect+0xd8/0x238) | [<8075a060>] (usb_disconnect) from [<8075a02c>] (usb_disconnect+0xa4/0x238) | [<8075a02c>] (usb_disconnect) from [<8075a02c>] (usb_disconnect+0xa4/0x238) | [<8075a02c>] (usb_disconnect) from [<80af3520>] (usb_remove_hcd+0xa0/0x198) | [<80af3520>] (usb_remove_hcd) from [<807902e0>] (host_stop+0x38/0xa8) | [<807902e0>] (host_stop) from [<8078d9e4>] (ci_hdrc_remove+0x3c/0x118) | [<8078d9e4>] (ci_hdrc_remove) from [<805b27ec>] (platform_remove+0x20/0x50) | [<805b27ec>] (platform_remove) from [<805b03a0>] (__device_release_driver+0x154/0x20c) | [<805b03a0>] (__device_release_driver) from [<805b0478>] (device_release_driver+0x20/0x2c) | [<805b0478>] (device_release_driver) from [<805af944>] (bus_remove_device+0xcc/0xf8) | [<805af944>] (bus_remove_device) from [<805ab26c>] (device_del+0x178/0x4b0) For this adapter we call ax88178_bind() and ax88772_unbind(), which is related to different chip version and different counter part *bind() function. Since this chip is currently not ported to the PHYLIB, we do not need to call phy_disconnect() here. So, to fix this crash, we need to add ax88178_unbind(). Fixes: e532a09 ("net: usb: asix: ax88772: add phylib support") Reported-by: Robin van der Gracht <robin@protonic.nl> Tested-by: Robin van der Gracht <robin@protonic.nl> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>

We update the ctime/mtime of a block device when we remove it so that blkid knows the device changed. However we do this by re-opening the block device and calling filp_update_time. This is more correct because it'll call the inode->i_op->update_time if it exists, but the block dev inodes do not do this. Instead call generic_update_time() on the bd_inode in order to avoid the blkdev_open path and get rid of the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#406 Not tainted ------------------------------------------------------ losetup/11596 is trying to acquire lock: ffff939640d2f538 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff939655510c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_get_by_dev.part.0+0x56/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 file_open_name+0xc7/0x170 filp_open+0x2c/0x50 btrfs_scratch_superblocks.part.0+0x10f/0x170 btrfs_rm_device.cold+0xe8/0xed btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11596: #0: ffff939655510c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 1 PID: 11596 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#406 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

When removing the device we call blkdev_put() on the device once we've removed it, and because we have an EXCL open we need to take the ->open_mutex on the block device to clean it up. Unfortunately during device remove we are holding the sb writers lock, which results in the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#407 Not tainted ------------------------------------------------------ losetup/11595 is trying to acquire lock: ffff973ac35dd138 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_put+0x3a/0x220 btrfs_rm_device.cold+0x62/0xe5 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11595: #0: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11595 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#407 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc21255d4cb So instead save the bdev and do the put once we've dropped the sb writers lock in order to avoid the lockdep recursion. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

If CONFIG_BLK_DEV_LOOP && CONFIG_MTD (at least; there might be other combinations), lockdep complains circular locking dependency at __loop_clr_fd(), for major_names_lock serves as a locking dependency aggregating hub across multiple block modules. ====================================================== WARNING: possible circular locking dependency detected 5.14.0+ torvalds#757 Tainted: G E ------------------------------------------------------ systemd-udevd/7568 is trying to acquire lock: ffff88800f334d48 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x70/0x560 but task is already holding lock: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&lo->lo_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_killable_nested+0x17/0x20 lo_open+0x23/0x50 [loop] blkdev_get_by_dev+0x199/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #5 (&disk->open_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 bd_register_pending_holders+0x20/0x100 device_add_disk+0x1ae/0x390 loop_add+0x29c/0x2d0 [loop] blk_request_module+0x5a/0xb0 blkdev_get_no_open+0x27/0xa0 blkdev_get_by_dev+0x5f/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #4 (major_names_lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 blkdev_show+0x19/0x80 devinfo_show+0x52/0x60 seq_read_iter+0x2d5/0x3e0 proc_reg_read_iter+0x41/0x80 vfs_read+0x2ac/0x330 ksys_read+0x6b/0xd0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&p->lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 seq_read_iter+0x37/0x3e0 generic_file_splice_read+0xf3/0x170 splice_direct_to_actor+0x14e/0x350 do_splice_direct+0x84/0xd0 do_sendfile+0x263/0x430 __se_sys_sendfile64+0x96/0xc0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#3){.+.+}-{0:0}: lock_acquire+0xbe/0x1f0 lo_write_bvec+0x96/0x280 [loop] loop_process_work+0xa68/0xc10 [loop] process_one_work+0x293/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: lock_acquire+0xbe/0x1f0 process_one_work+0x280/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: validate_chain+0x1f0d/0x33e0 __lock_acquire+0x92d/0x1030 lock_acquire+0xbe/0x1f0 flush_workqueue+0x8c/0x560 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 __loop_clr_fd+0xb4/0x400 [loop] blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 2 locks held by systemd-udevd/7568: #0: ffff888012554128 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x4c/0x1d0 #1: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] stack backtrace: CPU: 0 PID: 7568 Comm: systemd-udevd Tainted: G E 5.14.0+ torvalds#757 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020 Call Trace: dump_stack_lvl+0x79/0xbf print_circular_bug+0x5d6/0x5e0 ? stack_trace_save+0x42/0x60 ? save_trace+0x3d/0x2d0 check_noncircular+0x10b/0x120 validate_chain+0x1f0d/0x33e0 ? __lock_acquire+0x953/0x1030 ? __lock_acquire+0x953/0x1030 __lock_acquire+0x92d/0x1030 ? flush_workqueue+0x70/0x560 lock_acquire+0xbe/0x1f0 ? flush_workqueue+0x70/0x560 flush_workqueue+0x8c/0x560 ? flush_workqueue+0x70/0x560 ? sched_clock_cpu+0xe/0x1a0 ? drain_workqueue+0x41/0x140 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 ? blk_mq_freeze_queue_wait+0xac/0xd0 __loop_clr_fd+0xb4/0x400 [loop] ? __mutex_unlock_slowpath+0x35/0x230 blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0fd4c661f7 Code: 00 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 13 fc ff ff RSP: 002b:00007ffd1c9e9fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007f0fd46be6c8 RCX: 00007f0fd4c661f7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 0000000000000006 R08: 000055fff1eaf400 R09: 0000000000000000 R10: 00007f0fd46be6c8 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000002f08 R15: 00007ffd1c9ea050 Commit 1c500ad ("loop: reduce the loop_ctl_mutex scope") is for breaking "loop_ctl_mutex => &lo->lo_mutex" dependency chain. But enabling a different block module results in forming circular locking dependency due to shared major_names_lock mutex. The simplest fix is to call probe function without holding major_names_lock [1], but Christoph Hellwig does not like such idea. Therefore, instead of holding major_names_lock in blkdev_show(), introduce a different lock for blkdev_show() in order to break "sb_writers#$N => &p->lock => major_names_lock" dependency chain. Link: https://lkml.kernel.org/r/b2af8a5b-3c1b-204e-7f56-bea0b15848d6@i-love.sakura.ne.jp [1] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/18a02da2-0bf3-550e-b071-2b4ab13c49f0@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>

As previously noted in commit 66e4f4a ("rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()"): <4>[ 254.192378] WARNING: inconsistent lock state <4>[ 254.192384] 5.12.0-rc1-CI-CI_DRM_9834+ #1 Not tainted <4>[ 254.192396] -------------------------------- <4>[ 254.192400] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. <4>[ 254.192409] rtcwake/5309 [HC0[0]:SC0[0]:HE1:SE1] takes: <4>[ 254.192429] ffffffff8263c5f8 (rtc_lock){?...}-{2:2}, at: cmos_interrupt+0x18/0x100 <4>[ 254.192481] {IN-HARDIRQ-W} state was registered at: <4>[ 254.192488] lock_acquire+0xd1/0x3d0 <4>[ 254.192504] _raw_spin_lock+0x2a/0x40 <4>[ 254.192519] cmos_interrupt+0x18/0x100 <4>[ 254.192536] rtc_handler+0x1f/0xc0 <4>[ 254.192553] acpi_ev_fixed_event_detect+0x109/0x13c <4>[ 254.192574] acpi_ev_sci_xrupt_handler+0xb/0x28 <4>[ 254.192596] acpi_irq+0x13/0x30 <4>[ 254.192620] __handle_irq_event_percpu+0x43/0x2c0 <4>[ 254.192641] handle_irq_event_percpu+0x2b/0x70 <4>[ 254.192661] handle_irq_event+0x2f/0x50 <4>[ 254.192680] handle_fasteoi_irq+0x9e/0x150 <4>[ 254.192693] __common_interrupt+0x76/0x140 <4>[ 254.192715] common_interrupt+0x96/0xc0 <4>[ 254.192732] asm_common_interrupt+0x1e/0x40 <4>[ 254.192750] _raw_spin_unlock_irqrestore+0x38/0x60 <4>[ 254.192767] resume_irqs+0xba/0xf0 <4>[ 254.192786] dpm_resume_noirq+0x245/0x3d0 <4>[ 254.192811] suspend_devices_and_enter+0x230/0xaa0 <4>[ 254.192835] pm_suspend.cold.8+0x301/0x34a <4>[ 254.192859] state_store+0x7b/0xe0 <4>[ 254.192879] kernfs_fop_write_iter+0x11d/0x1c0 <4>[ 254.192899] new_sync_write+0x11d/0x1b0 <4>[ 254.192916] vfs_write+0x265/0x390 <4>[ 254.192933] ksys_write+0x5a/0xd0 <4>[ 254.192949] do_syscall_64+0x33/0x80 <4>[ 254.192965] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 254.192986] irq event stamp: 43775 <4>[ 254.192994] hardirqs last enabled at (43775): [<ffffffff81c00c42>] asm_sysvec_apic_timer_interrupt+0x12/0x20 <4>[ 254.193023] hardirqs last disabled at (43774): [<ffffffff81aa691a>] sysvec_apic_timer_interrupt+0xa/0xb0 <4>[ 254.193049] softirqs last enabled at (42548): [<ffffffff81e00342>] __do_softirq+0x342/0x48e <4>[ 254.193074] softirqs last disabled at (42543): [<ffffffff810b45fd>] irq_exit_rcu+0xad/0xd0 <4>[ 254.193101] other info that might help us debug this: <4>[ 254.193107] Possible unsafe locking scenario: <4>[ 254.193112] CPU0 <4>[ 254.193117] ---- <4>[ 254.193121] lock(rtc_lock); <4>[ 254.193137] <Interrupt> <4>[ 254.193142] lock(rtc_lock); <4>[ 254.193156] *** DEADLOCK *** <4>[ 254.193161] 6 locks held by rtcwake/5309: <4>[ 254.193174] #0: ffff888104861430 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x5a/0xd0 <4>[ 254.193232] #1: ffff88810f823288 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xe7/0x1c0 <4>[ 254.193282] #2: ffff888100cef3c0 (kn->active#285 <7>[ 254.192706] i915 0000:00:02.0: [drm:intel_modeset_setup_hw_state [i915]] [CRTC:51:pipe A] hw state readout: disabled <4>[ 254.193307] ){.+.+}-{0:0}, at: kernfs_fop_write_iter+0xf0/0x1c0 <4>[ 254.193333] #3: ffffffff82649fa8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend.cold.8+0xce/0x34a <4>[ 254.193387] #4: ffffffff827a2108 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x47/0x70 <4>[ 254.193433] #5: ffff8881019ea178 (&dev->mutex){....}-{3:3}, at: device_resume+0x68/0x1e0 <4>[ 254.193485] stack backtrace: <4>[ 254.193492] CPU: 1 PID: 5309 Comm: rtcwake Not tainted 5.12.0-rc1-CI-CI_DRM_9834+ #1 <4>[ 254.193514] Hardware name: Google Soraka/Soraka, BIOS MrChromebox-4.10 08/25/2019 <4>[ 254.193524] Call Trace: <4>[ 254.193536] dump_stack+0x7f/0xad <4>[ 254.193567] mark_lock.part.47+0x8ca/0xce0 <4>[ 254.193604] __lock_acquire+0x39b/0x2590 <4>[ 254.193626] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 <4>[ 254.193660] lock_acquire+0xd1/0x3d0 <4>[ 254.193677] ? cmos_interrupt+0x18/0x100 <4>[ 254.193716] _raw_spin_lock+0x2a/0x40 <4>[ 254.193735] ? cmos_interrupt+0x18/0x100 <4>[ 254.193758] cmos_interrupt+0x18/0x100 <4>[ 254.193785] cmos_resume+0x2ac/0x2d0 <4>[ 254.193813] ? acpi_pm_set_device_wakeup+0x1f/0x110 <4>[ 254.193842] ? pnp_bus_suspend+0x10/0x10 <4>[ 254.193864] pnp_bus_resume+0x5e/0x90 <4>[ 254.193885] dpm_run_callback+0x5f/0x240 <4>[ 254.193914] device_resume+0xb2/0x1e0 <4>[ 254.193942] ? pm_dev_err+0x25/0x25 <4>[ 254.193974] dpm_resume+0xea/0x3f0 <4>[ 254.194005] dpm_resume_end+0x8/0x10 <4>[ 254.194030] suspend_devices_and_enter+0x29b/0xaa0 <4>[ 254.194066] pm_suspend.cold.8+0x301/0x34a <4>[ 254.194094] state_store+0x7b/0xe0 <4>[ 254.194124] kernfs_fop_write_iter+0x11d/0x1c0 <4>[ 254.194151] new_sync_write+0x11d/0x1b0 <4>[ 254.194183] vfs_write+0x265/0x390 <4>[ 254.194207] ksys_write+0x5a/0xd0 <4>[ 254.194232] do_syscall_64+0x33/0x80 <4>[ 254.194251] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 254.194274] RIP: 0033:0x7f07d79691e7 <4>[ 254.194293] Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 <4>[ 254.194312] RSP: 002b:00007ffd9cc2c768 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 <4>[ 254.194337] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f07d79691e7 <4>[ 254.194352] RDX: 0000000000000004 RSI: 0000556ebfc63590 RDI: 000000000000000b <4>[ 254.194366] RBP: 0000556ebfc63590 R08: 0000000000000000 R09: 0000000000000004 <4>[ 254.194379] R10: 0000556ebf0ec2a6 R11: 0000000000000246 R12: 0000000000000004 which breaks S3-resume on fi-kbl-soraka presumably as that's slow enough to trigger the alarm during the suspend. Fixes: 6950d04 ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ") References: 66e4f4a ("rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()"): Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Xiaofei Tan <tanxiaofei@huawei.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20210305122140.28774-1-chris@chris-wilson.co.uk

It's later supposed to be either a correct address or NULL. Without the initialization, it may contain an undefined value which results in the following segmentation fault: # perf top --sort comm -g --ignore-callees=do_idle terminates with: #0 0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6 #1 0x00007ffff55e3802 in strdup () from /lib64/libc.so.6 #2 0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489 #3 hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564 #4 0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420, sample_self=sample_self@entry=true) at util/hist.c:657 #5 0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0, sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288 #6 0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38) at util/hist.c:1056 #7 iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056 #8 0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0) at util/hist.c:1231 #9 0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0) at builtin-top.c:842 #10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202 #11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244 #12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323 #13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339 #14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341 #15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339 #16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114 #17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0 #18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6 If you look at the frame #2, the code is: 488 if (he->srcline) { 489 he->srcline = strdup(he->srcline); 490 if (he->srcline == NULL) 491 goto err_rawdata; 492 } If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish), it gets strdupped and strdupping a rubbish random string causes the problem. Also, if you look at the commit 1fb7d06, it adds the srcline property into the struct, but not initializing it everywhere needed. Committer notes: Now I see, when using --ignore-callees=do_idle we end up here at line 2189 in add_callchain_ip(): 2181 if (al.sym != NULL) { 2182 if (perf_hpp_list.parent && !*parent && 2183 symbol__match_regex(al.sym, &parent_regex)) 2184 *parent = al.sym; 2185 else if (have_ignore_callees && root_al && 2186 symbol__match_regex(al.sym, &ignore_callees_regex)) { 2187 /* Treat this symbol as the root, 2188 forgetting its callees. */ 2189 *root_al = al; 2190 callchain_cursor_reset(cursor); 2191 } 2192 } And the al that doesn't have the ->srcline field initialized will be copied to the root_al, so then, back to: 1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al, 1212 int max_stack_depth, void *arg) 1213 { 1214 int err, err2; 1215 struct map *alm = NULL; 1216 1217 if (al) 1218 alm = map__get(al->map); 1219 1220 err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent, 1221 iter->evsel, al, max_stack_depth); 1222 if (err) { 1223 map__put(alm); 1224 return err; 1225 } 1226 1227 err = iter->ops->prepare_entry(iter, al); 1228 if (err) 1229 goto out; 1230 1231 err = iter->ops->add_single_entry(iter, al); 1232 if (err) 1233 goto out; 1234 That al at line 1221 is what hist_entry_iter__add() (called from sample__resolve_callchain()) saw as 'root_al', and then: iter->ops->add_single_entry(iter, al); will go on with al->srcline with a bogus value, I'll add the above sequence to the cset and apply, thanks! Signed-off-by: Michael Petlan <mpetlan@redhat.com> CC: Milian Wolff <milian.wolff@kdab.com> Cc: Jiri Olsa <jolsa@redhat.com> Fixes: 1fb7d06 ("perf report Use srcline from callchain for hist entries") Link: https //lore.kernel.org/r/20210719145332.29747-1-mpetlan@redhat.com Reported-by: Juri Lelli <jlelli@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

FD uses xyarray__entry that may return NULL if an index is out of bounds. If NULL is returned then a segv happens as FD unconditionally dereferences the pointer. This was happening in a case of with perf iostat as shown below. The fix is to make FD an "int*" rather than an int and handle the NULL case as either invalid input or a closed fd. $ sudo gdb --args perf stat --iostat list ... Breakpoint 1, perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50 50 { (gdb) bt #0 perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50 #1 0x000055555585c188 in evsel__open_cpu (evsel=0x5555560951a0, cpus=0x555556093410, threads=0x555556086fb0, start_cpu=0, end_cpu=1) at util/evsel.c:1792 #2 0x000055555585cfb2 in evsel__open (evsel=0x5555560951a0, cpus=0x0, threads=0x555556086fb0) at util/evsel.c:2045 #3 0x000055555585d0db in evsel__open_per_thread (evsel=0x5555560951a0, threads=0x555556086fb0) at util/evsel.c:2065 #4 0x00005555558ece64 in create_perf_stat_counter (evsel=0x5555560951a0, config=0x555555c34700 <stat_config>, target=0x555555c2f1c0 <target>, cpu=0) at util/stat.c:590 #5 0x000055555578e927 in __run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0) at builtin-stat.c:833 #6 0x000055555578f3c6 in run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0) at builtin-stat.c:1048 #7 0x0000555555792ee5 in cmd_stat (argc=1, argv=0x7fffffffe4a0) at builtin-stat.c:2534 #8 0x0000555555835ed3 in run_builtin (p=0x555555c3f540 <commands+288>, argc=3, argv=0x7fffffffe4a0) at perf.c:313 #9 0x0000555555836154 in handle_internal_command (argc=3, argv=0x7fffffffe4a0) at perf.c:365 #10 0x000055555583629f in run_argv (argcp=0x7fffffffe2ec, argv=0x7fffffffe2e0) at perf.c:409 #11 0x0000555555836692 in main (argc=3, argv=0x7fffffffe4a0) at perf.c:539 ... (gdb) c Continuing. Error: The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_iio_0/event=0x83,umask=0x04,ch_mask=0xF,fc_mask=0x07/). /bin/dmesg | grep -i perf may provide additional information. Program received signal SIGSEGV, Segmentation fault. 0x00005555559b03ea in perf_evsel__close_fd_cpu (evsel=0x5555560951a0, cpu=1) at evsel.c:166 166 if (FD(evsel, cpu, thread) >= 0) v3. fixes a bug in perf_evsel__run_ioctl where the sense of a branch was backward. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20210918054440.2350466-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Andrii Nakryiko says: ==================== Implement opt-in stricter BPF program section name (SEC()) handling logic. For a lot of supported ELF section names, enforce exact section name match with no arbitrary characters added at the end. See patch #9 for more details. To allow this, patches #2 through #4 clean up and preventively fix selftests, normalizing existing SEC() usage across multiple selftests. While at it, those patches also reduce the amount of remaining bpf_object__find_program_by_title() uses, which should be completely removed soon, given it's an API with ambiguous semantics and will be deprecated and eventually removed in libbpf 1.0. Patch #1 also introduces SEC("tc") as an alias for SEC("classifier"). "tc" is a better and less misleading name, so patch #3 replaces all classifier* uses with nice and short SEC("tc"). Last patch is also fixing "sk_lookup/" definition to not require and not allow extra "/blah" parts after it, which serve no meaning. All the other patches are gradual internal libbpf changes to: - allow this optional strict logic for ELF section name handling; - allow new use case (for now for "struct_ops", but that could be extended to, say, freplace definitions), in which it can be used stand-alone to specify just type (SEC("struct_ops")), or also accept extra parameters which can be utilized by libbpf to either get more data or double-check valid use (e.g., SEC("struct_ops/dctcp_init") to specify desired struct_ops operation that is supposed to be implemented); - get libbpf's internal logic ready to allow other libraries and applications to specify their custom handlers for ELF section name for BPF programs. All the pieces are in place, the only thing preventing making this as public libbpf API is reliance on internal type for specifying BPF program load attributes. The work is planned to revamp related low-level libbpf APIs, at which point it will be possible to just re-use such new types for coordination between libbpf and custom handlers. These changes are a part of libbpf 1.0 effort ([0]). They are also intended to be applied on top of the previous preparatory series [1], so currently CI will be failing to apply them to bpf-next until that patch set is landed. Once it is landed, kernel-patches daemon will automatically retest this patch set. [0] https://github.com/libbpf/libbpf/wiki/Libbpf:-the-road-to-v1.0#stricter-and-more-uniform-bpf-program-section-name-sec-handling [1] https://patchwork.kernel.org/project/netdevbpf/list/?series=547675&state=* v3->v4: - replace SEC("classifier*") with SEC("tc") (Daniel); v2->v3: - applied acks, addressed most feedback, added comments to new flags (Dave); v1->v2: - rebase onto latest bpf-next and resolve merge conflicts w/ Dave's changes. ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>

…r-mode' Ido Schimmel says: ==================== ethtool: Add ability to control transceiver modules' power mode This patchset extends the ethtool netlink API to allow user space to control transceiver modules. Two specific APIs are added, but the plan is to extend the interface with more APIs in the future (see "Future plans"). This submission is a complete rework of a previous submission [1] that tried to achieve the same goal by allowing user space to write to the EEPROMs of these modules. It was rejected as it could have enabled user space binary blob drivers. However, the main issue is that by directly writing to some pages of these EEPROMs, we are interfering with the entity that is controlling the modules (kernel / device firmware). In addition, some functionality cannot be implemented solely by writing to the EEPROM, as it requires the assertion / de-assertion of hardware signals (e.g., "ResetL" pin in SFF-8636). Motivation ========== The kernel can currently dump the contents of module EEPROMs to user space via the ethtool legacy ioctl API or the new netlink API. These dumps can then be parsed by ethtool(8) according to the specification that defines the memory map of the EEPROM. For example, SFF-8636 [2] for QSFP and CMIS [3] for QSFP-DD. In addition to read-only elements, these specifications also define writeable elements that can be used to control the behavior of the module. For example, controlling whether the module is put in low or high power mode to limit its power consumption. The CMIS specification even defines a message exchange mechanism (CDB, Command Data Block) on top of the module's memory map. This allows the host to send various commands to the module. For example, to update its firmware. Implementation ============== The ethtool netlink API is extended with two new messages, 'ETHTOOL_MSG_MODULE_SET' and 'ETHTOOL_MSG_MODULE_GET', that allow user space to set and get transceiver module parameters. Specifically, the 'ETHTOOL_A_MODULE_POWER_MODE_POLICY' attribute allows user space to control the power mode policy of the module in order to limit its power consumption. See detailed description in patch #1. The user API is designed to be generic enough so that it could be used for modules with different memory maps (e.g., SFF-8636, CMIS). The only implementation of the device driver API in this series is for a MAC driver (mlxsw) where the module is controlled by the device's firmware, but it is designed to be generic enough so that it could also be used by implementations where the module is controlled by the kernel. Testing and introspection ========================= See detailed description in patches #1 and #5. Patchset overview ================= Patch #1 adds the initial infrastructure in ethtool along with the ability to control transceiver modules' power mode. Patches #2-#3 add required device registers in mlxsw. Patch #4 implements in mlxsw the ethtool operations added in patch #1. Patch #5 adds extended link states in order to allow user space to troubleshoot link down issues related to transceiver modules. Patch #6 adds support for these extended states in mlxsw. Future plans ============ * Extend 'ETHTOOL_MSG_MODULE_SET' to control Tx output among other attributes. * Add new ethtool message(s) to update firmware on transceiver modules. * Extend ethtool(8) to parse more diagnostic information from CMIS modules. No kernel changes required. [1] https://lore.kernel.org/netdev/20210623075925.2610908-1-idosch@idosch.org/ [2] https://members.snia.org/document/dl/26418 [3] http://www.qsfp-dd.com/wp-content/uploads/2021/05/CMIS5p0.pdf Previous versions: [4] https://lore.kernel.org/netdev/20211003073219.1631064-1-idosch@idosch.org/ [5] https://lore.kernel.org/netdev/20210824130344.1828076-1-idosch@idosch.org/ [6] https://lore.kernel.org/netdev/20210818155202.1278177-1-idosch@idosch.org/ [7] https://lore.kernel.org/netdev/20210809102152.719961-1-idosch@idosch.org/ ==================== Link: https://lore.kernel.org/r/20211006104647.2357115-1-idosch@idosch.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pablo Neira Ayuso says: ==================== Netfilter fixes for net (v2) The following patchset contains Netfilter fixes for net: 1) Move back the defrag users fields to the global netns_nf area. Kernel fails to boot if conntrack is builtin and kernel is booted with: nf_conntrack.enable_hooks=1. From Florian Westphal. 2) Rule event notification is missing relevant context such as the position handle and the NLM_F_APPEND flag. 3) Rule replacement is expanded to add + delete using the existing rule handle, reverse order of this operation so it makes sense from rule notification standpoint. 4) Propagate to userspace the NLM_F_CREATE and NLM_F_EXCL flags from the rule notification path. Patches #2, #3 and #4 are used by 'nft monitor' and 'iptables-monitor' userspace utilities which are not correctly representing the following operations through netlink notifications: - rule insertions - rule addition/insertion from position handle - create table/chain/set/map/flowtable/... ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says: ==================== selftests: forwarding: Add ip6gre tests This patchset adds forwarding selftests for ip6gre. The tests can be run with veth pairs or with physical loopbacks. Patch #1 adds a new config option to determine if 'skip_sw' / 'skip_hw' flags are used when installing tc filters. By default, it is not set which means the flags are not used. 'skip_sw' is useful to ensure traffic is forwarded by the hardware data path. Patch #2 adds a new helper function. Patches #3-#4 add the forwarding selftests. Patch #5 adds a mlxsw-specific selftest to validate correct behavior of the 'decap_error' trap with IPv6 underlay. Patches #6-#8 align the corresponding IPv4 underlay test to the IPv6 one. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says: ==================== mlxsw: Add support for ECN mirroring Petr says: Patches in this set have been floating around for some time now together with trap_fwd support. That will however need more work, time for which is nowhere to be found, apparently. Instead, this patchset enables offload of only packet mirroring on RED mark qevent, enabling mirroring of ECN-marked packets. Formally it enables offload of filters added to blocks bound to the RED qevent mark if: - The switch ASIC is Spectrum-2 or above. - Only a single filter is attached at the block, at chain 0 (the default), and its classifier is matchall. - The filter has hw_stats set to disabled. - The filter has a single action, which is mirror. This differs from early_drop qevent offload, which supports mirroring and trapping. However trapping in context of ECN-marked packets is not suitable, because the HW does not drop the packet, as the trap action implies. And there is as of now no way to express only the part of trapping that transfers the packet to the SW datapath, sans the HW-datapath drop. The patchset progresses as follows: Patch #1 is an extack propagation. Mirroring of ECN-marked packets is configured in the ASIC through an ECN trigger, which is considered "egress", unlike the EARLY_DROP trigger. In patch #2, add a helper to classify triggers as ingress. As clarified above, traps cannot be offloaded on mark qevent. Similarly, given a trap_fwd action, it would not be offloadable on early_drop qevent. In patch #3, introduce support for tracking actions permissible on a given block. Patch #4 actually adds the mark qevent offload. In patch #5, fix a small style issue in one of the selftests, and in patch #6 add mark offload selftests. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says: ==================== mlxsw: Multi-level qdisc offload Petr says: Currently, mlxsw admits for offload a suitable root qdisc, and its children. Thus up to two levels of hierarchy are offloaded. Often, this is enough: one can configure TCs with RED and TCs with a shaper on, and can even see counters for each TC by looking at a qdisc at a sufficiently shallow position. While simple, the system has obvious shortcomings. It is not possible to configure both RED and shaping on one TC. It is not possible to place a PRIO below root TBF, which would then be offloaded as port shaper. FIFOs are only offloaded at root or directly below, which is confusing to users, because RED and TBF of course have their own FIFO. This patch set lifts assumptions that prevent offloading multi-level qdisc trees. In patch #1, offload of a graft operation is added to TBF. Grafts are issued as another qdisc is linked to the qdisc in question, and give drivers a chance to react to the linking. The absence of this event was not a major issue so far, because TBF was not considered classful, which changes with this patchset. The codebase currently assumes that ETS and PRIO are the only classful qdiscs. The following patches gradually lift this assumption. In patch #2, calculation of traffic class and priomap of a qdisc is fixed. Patch #3 fixes handling of future FIFOs. Child FIFO qdiscs may be created and notified before their parent qdisc exists and therefore need special handling. Patches #4, #5 and #6 unify, respectively, child destruction, child grafting, and cleanup of statistics. Patch #7 adds a function that validates whether a given qdisc topology is offloadable. Finally in patch #8, TBF and RED become classful. At this point, FIFO qdiscs grafted to an offloaded qdisc should always be offloaded. Patch #9 adds a selftest to verify some offloadable and unoffloadable qdisc trees. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

There is no devfreq on a3xx at the moment since gpu_busy is not implemented. This means that msm_devfreq_init() will return early and the entire devfreq setup is skipped. However, msm_devfreq_active() and msm_devfreq_idle() are still called unconditionally later, causing a NULL pointer dereference: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 Internal error: Oops: 96000004 [#1] PREEMPT SMP CPU: 0 PID: 133 Comm: ring0 Not tainted 5.15.0-rc1 #4 Hardware name: Longcheer L8150 (DT) pc : mutex_lock_io+0x2bc/0x2f0 lr : msm_devfreq_active+0x3c/0xe0 [msm] Call trace: mutex_lock_io+0x2bc/0x2f0 msm_gpu_submit+0x164/0x180 [msm] msm_job_run+0x54/0xe0 [msm] drm_sched_main+0x2b0/0x4a0 [gpu_sched] kthread+0x154/0x160 ret_from_fork+0x10/0x20 Fix this by adding a check in msm_devfreq_active/idle() which ensures that devfreq was actually initialized earlier. Fixes: 9bc9557 ("drm/msm: Devfreq tuning") Reported-by: Nikita Travkin <nikita@trvn.ru> Tested-by: Nikita Travkin <nikita@trvn.ru> Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Link: https://lore.kernel.org/r/20210913164556.16284-1-stephan@gerhold.net Signed-off-by: Rob Clark <robdclark@chromium.org>

Ido Schimmel says: ==================== mlxsw: Support multiple RIF MAC prefixes Currently, mlxsw enforces that all the netdevs used as router interfaces (RIFs) have the same MAC prefix (e.g., same 38 MSBs in Spectrum-1). Otherwise, an error is returned to user space with extack. This patchset relaxes the limitation through the use of RIF MAC profiles. A RIF MAC profile is a hardware entity that represents a particular MAC prefix which multiple RIFs can reference. Therefore, the number of possible MAC prefixes is no longer one, but the number of profiles supported by the device. The ability to change the MAC of a particular netdev is useful, for example, for users who use the netdev to connect to an upstream provider that performs MAC filtering. Currently, such users are either forced to negotiate with the provider or change the MAC address of all other netdevs so that they share the same prefix. Patchset overview: Patches #1-#3 are preparations. Patch #4 adds actual support for RIF MAC profiles. Patch #5 exposes RIF MAC profiles as a devlink resource, so that user space has visibility into the maximum number of profiles and current occupancy. Useful for debugging and testing (next 3 patches). Patches #6-#8 add both scale and functional tests. Patch #9 removes tests that validated the previous limitation. It is now covered by patch #6 for devices that support a single profile. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

We got the following lockdep splat while running fstests (specifically btrfs/003 and btrfs/020 in a row) with the new rc. This was uncovered by 87579e9 ("loop: use worker per cgroup instead of kworker") which converted loop to using workqueues, which comes with lockdep annotations that don't exist with kworkers. The lockdep splat is as follows: WARNING: possible circular locking dependency detected 5.14.0-rc2-custom+ torvalds#34 Not tainted ------------------------------------------------------ losetup/156417 is trying to acquire lock: ffff9c7645b02d38 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x84/0x600 but task is already holding lock: ffff9c7647395468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x650 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0xba/0x7c0 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x28/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x163/0x3a0 path_openat+0x74d/0xa40 do_filp_open+0x9c/0x140 do_sys_openat2+0xb1/0x170 __x64_sys_openat+0x54/0x90 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #4 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0xba/0x7c0 blkdev_get_by_dev.part.0+0xd1/0x3c0 blkdev_get_by_path+0xc0/0xd0 btrfs_scan_one_device+0x52/0x1f0 [btrfs] btrfs_control_ioctl+0xac/0x170 [btrfs] __x64_sys_ioctl+0x83/0xb0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (uuid_mutex){+.+.}-{3:3}: __mutex_lock+0xba/0x7c0 btrfs_rm_device+0x48/0x6a0 [btrfs] btrfs_ioctl+0x2d1c/0x3110 [btrfs] __x64_sys_ioctl+0x83/0xb0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#11){.+.+}-{0:0}: lo_write_bvec+0x112/0x290 [loop] loop_process_work+0x25f/0xcb0 [loop] process_one_work+0x28f/0x5d0 worker_thread+0x55/0x3c0 kthread+0x140/0x170 ret_from_fork+0x22/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x266/0x5d0 worker_thread+0x55/0x3c0 kthread+0x140/0x170 ret_from_fork+0x22/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x1130/0x1dc0 lock_acquire+0xf5/0x320 flush_workqueue+0xae/0x600 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x650 [loop] lo_ioctl+0x29d/0x780 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x83/0xb0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/156417: #0: ffff9c7647395468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x650 [loop] stack backtrace: CPU: 8 PID: 156417 Comm: losetup Not tainted 5.14.0-rc2-custom+ torvalds#34 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0x10a/0x120 __lock_acquire+0x1130/0x1dc0 lock_acquire+0xf5/0x320 ? flush_workqueue+0x84/0x600 flush_workqueue+0xae/0x600 ? flush_workqueue+0x84/0x600 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x650 [loop] lo_ioctl+0x29d/0x780 [loop] ? __lock_acquire+0x3a0/0x1dc0 ? update_dl_rq_load_avg+0x152/0x360 ? lock_is_held_type+0xa5/0x120 ? find_held_lock.constprop.0+0x2b/0x80 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x83/0xb0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f645884de6b Usually the uuid_mutex exists to protect the fs_devices that map together all of the devices that match a specific uuid. In rm_device we're messing with the uuid of a device, so it makes sense to protect that here. However in doing that it pulls in a whole host of lockdep dependencies, as we call mnt_may_write() on the sb before we grab the uuid_mutex, thus we end up with the dependency chain under the uuid_mutex being added under the normal sb write dependency chain, which causes problems with loop devices. We don't need the uuid mutex here however. If we call btrfs_scan_one_device() before we scratch the super block we will find the fs_devices and not find the device itself and return EBUSY because the fs_devices is open. If we call it after the scratch happens it will not appear to be a valid btrfs file system. We do not need to worry about other fs_devices modifying operations here because we're protected by the exclusive operations locking. So drop the uuid_mutex here in order to fix the lockdep splat. A more detailed explanation from the discussion: We are worried about rm and scan racing with each other, before this change we'll zero the device out under the UUID mutex so when scan does run it'll make sure that it can go through the whole device scan thing without rm messing with us. We aren't worried if the scratch happens first, because the result is we don't think this is a btrfs device and we bail out. The only case we are concerned with is we scratch _after_ scan is able to read the superblock and gets a seemingly valid super block, so lets consider this case. Scan will call device_list_add() with the device we're removing. We'll call find_fsid_with_metadata_uuid() and get our fs_devices for this UUID. At this point we lock the fs_devices->device_list_mutex. This is what protects us in this case, but we have two cases here. 1. We aren't to the device removal part of the RM. We found our device, and device name matches our path, we go down and we set total_devices to our super number of devices, which doesn't affect anything because we haven't done the remove yet. 2. We are past the device removal part, which is protected by the device_list_mutex. Scan doesn't find the device, it goes down and does the if (fs_devices->opened) return -EBUSY; check and we bail out. Nothing about this situation is ideal, but the lockdep splat is real, and the fix is safe, tho admittedly a bit scary looking. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ copy more from the discussion ] Signed-off-by: David Sterba <dsterba@suse.com>

For device removal and replace we call btrfs_find_device_by_devspec, which if we give it a device path and nothing else will call btrfs_get_dev_args_from_path, which opens the block device and reads the super block and then looks up our device based on that. However at this point we're holding the sb write "lock", so reading the block device pulls in the dependency of ->open_mutex, which produces the following lockdep splat ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#405 Not tainted ------------------------------------------------------ losetup/11576 is trying to acquire lock: ffff9bbe8cded938 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff9bbe88e4fc68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_get_by_dev.part.0+0x56/0x3c0 blkdev_get_by_path+0x98/0xa0 btrfs_get_bdev_and_sb+0x1b/0xb0 btrfs_find_device_by_devspec+0x12b/0x1c0 btrfs_rm_device+0x127/0x610 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11576: #0: ffff9bbe88e4fc68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11576 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#405 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f31b02404cb Instead what we want to do is populate our device lookup args before we grab any locks, and then pass these args into btrfs_rm_device(). From there we can find the device and do the appropriate removal. Suggested-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>

Attempting to defragment a Btrfs file containing a transparent huge page immediately deadlocks with the following stack trace: #0 context_switch (kernel/sched/core.c:4940:2) #1 __schedule (kernel/sched/core.c:6287:8) #2 schedule (kernel/sched/core.c:6366:3) #3 io_schedule (kernel/sched/core.c:8389:2) #4 wait_on_page_bit_common (mm/filemap.c:1356:4) #5 __lock_page (mm/filemap.c:1648:2) #6 lock_page (./include/linux/pagemap.h:625:3) #7 pagecache_get_page (mm/filemap.c:1910:4) #8 find_or_create_page (./include/linux/pagemap.h:420:9) #9 defrag_prepare_one_page (fs/btrfs/ioctl.c:1068:9) #10 defrag_one_range (fs/btrfs/ioctl.c:1326:14) #11 defrag_one_cluster (fs/btrfs/ioctl.c:1421:9) #12 btrfs_defrag_file (fs/btrfs/ioctl.c:1523:9) #13 btrfs_ioctl_defrag (fs/btrfs/ioctl.c:3117:9) #14 btrfs_ioctl (fs/btrfs/ioctl.c:4872:10) #15 vfs_ioctl (fs/ioctl.c:51:10) #16 __do_sys_ioctl (fs/ioctl.c:874:11) #17 __se_sys_ioctl (fs/ioctl.c:860:1) #18 __x64_sys_ioctl (fs/ioctl.c:860:1) #19 do_syscall_x64 (arch/x86/entry/common.c:50:14) #20 do_syscall_64 (arch/x86/entry/common.c:80:7) #21 entry_SYSCALL_64+0x7c/0x15b (arch/x86/entry/entry_64.S:113) A huge page is represented by a compound page, which consists of a struct page for each PAGE_SIZE page within the huge page. The first struct page is the "head page", and the remaining are "tail pages". Defragmentation attempts to lock each page in the range. However, lock_page() on a tail page actually locks the corresponding head page. So, if defragmentation tries to lock more than one struct page in a compound page, it tries to lock the same head page twice and deadlocks with itself. Ideally, we should be able to defragment transparent huge pages. However, THP for filesystems is currently read-only, so a lot of code is not ready to use huge pages for I/O. For now, let's just return ETXTBUSY. This can be reproduced with the following on a kernel with CONFIG_READ_ONLY_THP_FOR_FS=y: $ cat create_thp_file.c #include <fcntl.h> #include <stdbool.h> #include <stdio.h> #include <stdint.h> #include <stdlib.h> #include <unistd.h> #include <sys/mman.h> static const char zeroes[1024 * 1024]; static const size_t FILE_SIZE = 2 * 1024 * 1024; int main(int argc, char **argv) { if (argc != 2) { fprintf(stderr, "usage: %s PATH\n", argv[0]); return EXIT_FAILURE; } int fd = creat(argv[1], 0777); if (fd == -1) { perror("creat"); return EXIT_FAILURE; } size_t written = 0; while (written < FILE_SIZE) { ssize_t ret = write(fd, zeroes, sizeof(zeroes) < FILE_SIZE - written ? sizeof(zeroes) : FILE_SIZE - written); if (ret < 0) { perror("write"); return EXIT_FAILURE; } written += ret; } close(fd); fd = open(argv[1], O_RDONLY); if (fd == -1) { perror("open"); return EXIT_FAILURE; } /* * Reserve some address space so that we can align the file mapping to * the huge page size. */ void *placeholder_map = mmap(NULL, FILE_SIZE * 2, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (placeholder_map == MAP_FAILED) { perror("mmap (placeholder)"); return EXIT_FAILURE; } void *aligned_address = (void *)(((uintptr_t)placeholder_map + FILE_SIZE - 1) & ~(FILE_SIZE - 1)); void *map = mmap(aligned_address, FILE_SIZE, PROT_READ | PROT_EXEC, MAP_SHARED | MAP_FIXED, fd, 0); if (map == MAP_FAILED) { perror("mmap"); return EXIT_FAILURE; } if (madvise(map, FILE_SIZE, MADV_HUGEPAGE) < 0) { perror("madvise"); return EXIT_FAILURE; } char *line = NULL; size_t line_capacity = 0; FILE *smaps_file = fopen("/proc/self/smaps", "r"); if (!smaps_file) { perror("fopen"); return EXIT_FAILURE; } for (;;) { for (size_t off = 0; off < FILE_SIZE; off += 4096) ((volatile char *)map)[off]; ssize_t ret; bool this_mapping = false; while ((ret = getline(&line, &line_capacity, smaps_file)) > 0) { unsigned long start, end, huge; if (sscanf(line, "%lx-%lx", &start, &end) == 2) { this_mapping = (start <= (uintptr_t)map && (uintptr_t)map < end); } else if (this_mapping && sscanf(line, "FilePmdMapped: %ld", &huge) == 1 && huge > 0) { return EXIT_SUCCESS; } } sleep(6); rewind(smaps_file); fflush(smaps_file); } } $ ./create_thp_file huge $ btrfs fi defrag -czstd ./huge Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

Convert the netfs helper library to use folios throughout, convert the 9p and afs filesystems to use folios in their file I/O paths and convert the ceph filesystem to use just enough folios to compile. With these changes, afs passes -g quick xfstests. Changes ======= ver #5: - Got rid of folio_end{io,_read,_write}() and inlined the stuff it does instead (Willy decided he didn't want this after all). ver #4: - Fixed a bug in afs_redirty_page() whereby it didn't set the next page index in the loop and returned too early. - Simplified a check in v9fs_vfs_write_folio_locked()[1]. - Undid a change to afs_symlink_readpage()[1]. - Used offset_in_folio() in afs_write_end()[1]. - Changed from using page_endio() to folio_end{io,_read,_write}()[1]. ver #2: - Add 9p foliation. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dominique Martinet <asmadeus@codewreck.org> Tested-by: kafs-testing@auristor.com cc: Matthew Wilcox (Oracle) <willy@infradead.org> cc: Marc Dionne <marc.dionne@auristor.com> cc: Ilya Dryomov <idryomov@gmail.com> cc: Dominique Martinet <asmadeus@codewreck.org> cc: v9fs-developer@lists.sourceforge.net cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/YYKa3bfQZxK5/wDN@casper.infradead.org/ [1] Link: https://lore.kernel.org/r/2408234.1628687271@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/162877311459.3085614.10601478228012245108.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/162981153551.1901565.3124454657133703341.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/163005745264.2472992.9852048135392188995.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163584187452.4023316.500389675405550116.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/163649328026.309189.1124218109373941936.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/163657852454.834781.9265101983152100556.stgit@warthog.procyon.org.uk/ # v5

The exit function fixes a memory leak with the src field as detected by leak sanitizer. An example of which is: Indirect leak of 25133184 byte(s) in 207 object(s) allocated from: #0 0x7f199ecfe987 in __interceptor_calloc libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x55defe638224 in annotated_source__alloc_histograms util/annotate.c:803 #2 0x55defe6397e4 in symbol__hists util/annotate.c:952 #3 0x55defe639908 in symbol__inc_addr_samples util/annotate.c:968 #4 0x55defe63aa29 in hist_entry__inc_addr_samples util/annotate.c:1119 #5 0x55defe499a79 in hist_iter__report_callback tools/perf/builtin-report.c:182 #6 0x55defe7a859d in hist_entry_iter__add util/hist.c:1236 #7 0x55defe49aa63 in process_sample_event tools/perf/builtin-report.c:315 #8 0x55defe731bc8 in evlist__deliver_sample util/session.c:1473 #9 0x55defe731e38 in machines__deliver_event util/session.c:1510 #10 0x55defe732a23 in perf_session__deliver_event util/session.c:1590 #11 0x55defe72951e in ordered_events__deliver_event util/session.c:183 #12 0x55defe740082 in do_flush util/ordered-events.c:244 #13 0x55defe7407cb in __ordered_events__flush util/ordered-events.c:323 #14 0x55defe740a61 in ordered_events__flush util/ordered-events.c:341 #15 0x55defe73837f in __perf_session__process_events util/session.c:2390 #16 0x55defe7385ff in perf_session__process_events util/session.c:2420 ... Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin Liška <mliska@suse.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20211112035124.94327-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

[BUG] The following script can cause btrfs to crash: $ mount -o compress-force=lzo $DEV /mnt $ dd if=/dev/urandom of=/mnt/foo bs=4k count=1 $ sync The call trace looks like this: general protection fault, probably for non-canonical address 0xe04b37fccce3b000: 0000 [#1] PREEMPT SMP NOPTI CPU: 5 PID: 164 Comm: kworker/u20:3 Not tainted 5.15.0-rc7-custom+ #4 Workqueue: btrfs-delalloc btrfs_work_helper [btrfs] RIP: 0010:__memcpy+0x12/0x20 Call Trace: lzo_compress_pages+0x236/0x540 [btrfs] btrfs_compress_pages+0xaa/0xf0 [btrfs] compress_file_range+0x431/0x8e0 [btrfs] async_cow_start+0x12/0x30 [btrfs] btrfs_work_helper+0xf6/0x3e0 [btrfs] process_one_work+0x294/0x5d0 worker_thread+0x55/0x3c0 kthread+0x140/0x170 ret_from_fork+0x22/0x30 ---[ end trace 63c3c0f131e61982 ]--- [CAUSE] In lzo_compress_pages(), parameter @out_pages is not only an output parameter (for the number of compressed pages), but also an input parameter, as the upper limit of compressed pages we can utilize. In commit d408880 ("btrfs: subpage: make lzo_compress_pages() compatible"), the refactoring doesn't take @out_pages as an input, thus completely ignoring the limit. And for compress-force case, we could hit incompressible data that compressed size would go beyond the page limit, and cause the above crash. [FIX] Save @out_pages as @max_nr_page, and pass it to lzo_compress_pages(), and check if we're beyond the limit before accessing the pages. Note: this also fixes crash on 32bit architectures that was suspected to be caused by merge of btrfs patches to 5.16-rc1. Reported in https://lore.kernel.org/all/20211104115001.GU20319@twin.jikos.cz/ . Reported-by: Omar Sandoval <osandov@fb.com> Fixes: d408880 ("btrfs: subpage: make lzo_compress_pages() compatible") Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add note ] Signed-off-by: David Sterba <dsterba@suse.com>

Line 1169 (#3) allocates a memory chunk for victim_name by kmalloc(), but when the function returns in line 1184 (#4) victim_name allocated by line 1169 (#3) is not freed, which will lead to a memory leak. There is a similar snippet of code in this function as allocating a memory chunk for victim_name in line 1104 (#1) as well as releasing the memory in line 1116 (#2). We should kfree() victim_name when the return value of backref_in_log() is less than zero and before the function returns in line 1184 (#4). 1057 static inline int __add_inode_ref(struct btrfs_trans_handle *trans, 1058 struct btrfs_root *root, 1059 struct btrfs_path *path, 1060 struct btrfs_root *log_root, 1061 struct btrfs_inode *dir, 1062 struct btrfs_inode *inode, 1063 u64 inode_objectid, u64 parent_objectid, 1064 u64 ref_index, char *name, int namelen, 1065 int *search_done) 1066 { 1104 victim_name = kmalloc(victim_name_len, GFP_NOFS); // #1: kmalloc (victim_name-1) 1105 if (!victim_name) 1106 return -ENOMEM; 1112 ret = backref_in_log(log_root, &search_key, 1113 parent_objectid, victim_name, 1114 victim_name_len); 1115 if (ret < 0) { 1116 kfree(victim_name); // #2: kfree (victim_name-1) 1117 return ret; 1118 } else if (!ret) { 1169 victim_name = kmalloc(victim_name_len, GFP_NOFS); // #3: kmalloc (victim_name-2) 1170 if (!victim_name) 1171 return -ENOMEM; 1180 ret = backref_in_log(log_root, &search_key, 1181 parent_objectid, victim_name, 1182 victim_name_len); 1183 if (ret < 0) { 1184 return ret; // #4: missing kfree (victim_name-2) 1185 } else if (!ret) { 1241 return 0; 1242 } Fixes: d3316c8 ("btrfs: Properly handle backref_in_log retval") CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Jianglei Nie <niejianglei2021@163.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

The fixed commit attempts to close inject.output even if it was never opened e.g. $ perf record uname Linux [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.002 MB perf.data (7 samples) ] $ perf inject -i perf.data --vm-time-correlation=dry-run Segmentation fault (core dumped) $ gdb --quiet perf Reading symbols from perf... (gdb) r inject -i perf.data --vm-time-correlation=dry-run Starting program: /home/ahunter/bin/perf inject -i perf.data --vm-time-correlation=dry-run [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. 0x00007eff8afeef5b in _IO_new_fclose (fp=0x0) at iofclose.c:48 48 iofclose.c: No such file or directory. (gdb) bt #0 0x00007eff8afeef5b in _IO_new_fclose (fp=0x0) at iofclose.c:48 #1 0x0000557fc7b74f92 in perf_data__close (data=data@entry=0x7ffcdafa6578) at util/data.c:376 #2 0x0000557fc7a6b807 in cmd_inject (argc=<optimized out>, argv=<optimized out>) at builtin-inject.c:1085 #3 0x0000557fc7ac4783 in run_builtin (p=0x557fc8074878 <commands+600>, argc=4, argv=0x7ffcdafb6a60) at perf.c:313 #4 0x0000557fc7a25d5c in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:365 #5 run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:409 #6 main (argc=4, argv=0x7ffcdafb6a60) at perf.c:539 (gdb) Fixes: 02e6246 ("perf inject: Close inject.output on exit") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: stable@vger.kernel.org Link: http://lore.kernel.org/lkml/20211213084829.114772-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The fixed commit attempts to get the output file descriptor even if the file was never opened e.g. $ perf record uname Linux [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.002 MB perf.data (7 samples) ] $ perf inject -i perf.data --vm-time-correlation=dry-run Segmentation fault (core dumped) $ gdb --quiet perf Reading symbols from perf... (gdb) r inject -i perf.data --vm-time-correlation=dry-run Starting program: /home/ahunter/bin/perf inject -i perf.data --vm-time-correlation=dry-run [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. __GI___fileno (fp=0x0) at fileno.c:35 35 fileno.c: No such file or directory. (gdb) bt #0 __GI___fileno (fp=0x0) at fileno.c:35 #1 0x00005621e48dd987 in perf_data__fd (data=0x7fff4c68bd08) at util/data.h:72 #2 perf_data__fd (data=0x7fff4c68bd08) at util/data.h:69 #3 cmd_inject (argc=<optimized out>, argv=0x7fff4c69c1f0) at builtin-inject.c:1017 #4 0x00005621e4936783 in run_builtin (p=0x5621e4ee6878 <commands+600>, argc=4, argv=0x7fff4c69c1f0) at perf.c:313 #5 0x00005621e4897d5c in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:365 #6 run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:409 #7 main (argc=4, argv=0x7fff4c69c1f0) at perf.c:539 (gdb) Fixes: 0ae0389 ("perf tools: Pass a fd to perf_file_header__read_pipe()") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: stable@vger.kernel.org Link: http://lore.kernel.org/lkml/20211213084829.114772-3-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Ido Schimmel says: ==================== mlxsw: devlink health reporter extensions This patchset extends the devlink health reporter registered by mlxsw to report new health events and their related parameters. These are meant to aid in debugging hardware and firmware issues. Patches #1-#2 are preparations. Patch #3 adds the definitions of the new events and parameters. Patch #4 extends the health reporter to report the new events and parameters. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

Amit Cohen says: ==================== Add tests for VxLAN with IPv6 underlay mlxsw driver lately added support for VxLAN with IPv6 underlay. This set adds the relevant tests for IPv6, most of them are same to IPv4 tests with the required changes. Patch set overview: Patch #1 relaxes requirements for offloading TC filters that match on 802.1q fields. The following selftests make use of these newly-relaxed filters. Patch #2 adds preparation as part of selftests API, which will be used later. Patches #3-#4 add tests for VxLAN with bridge aware and unaware. Patche #5 cleans unused function. Patches #6-#7 add tests for VxLAN symmetric and asymmetric. Patch #8 adds test for Q-in-VNI. ==================== Link: https://lore.kernel.org/r/20211221144949.2527545-1-amcohen@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

…uctions Add several ./test_progs tests: - arena_atomics/load_acquire - arena_atomics/store_release - verifier_load_acquire/* - verifier_store_release/* - verifier_precision/bpf_load_acquire - verifier_precision/bpf_store_release The last two tests are added to check if backtrack_insn() handles the new instructions correctly. Additionally, the last test also makes sure that the verifier "remembers" the value (in src_reg) we store-release into e.g. a stack slot. For example, if we take a look at the test program: #0: r1 = 8; /* store_release((u64 *)(r10 - 8), r1); */ #1: .8byte %[store_release]; #2: r1 = *(u64 *)(r10 - 8); #3: r2 = r10; #4: r2 += r1; #5: r0 = 0; #6: exit; At #1, if the verifier doesn't remember that we wrote 8 to the stack, then later at #4 we would be adding an unbounded scalar value to the stack pointer, which would cause the program to be rejected: VERIFIER LOG: ============= ... math between fp pointer and register with unbounded min value is not allowed For easier CI integration, instead of using built-ins like __atomic_{load,store}_n() which depend on the new __BPF_FEATURE_LOAD_ACQ_STORE_REL pre-defined macro, manually craft load-acquire/store-release instructions using __imm_insn(), as suggested by Eduard. All new tests depend on: (1) Clang major version >= 18, and (2) ENABLE_ATOMICS_TESTS is defined (currently implies -mcpu=v3 or v4), and (3) JIT supports load-acquire/store-release (currently arm64 and x86-64) In .../progs/arena_atomics.c: /* 8-byte-aligned */ __u8 __arena_global load_acquire8_value = 0x12; /* 1-byte hole */ __u16 __arena_global load_acquire16_value = 0x1234; That 1-byte hole in the .addr_space.1 ELF section caused clang-17 to crash: fatal error: error in backend: unable to write nop sequence of 1 bytes To work around such llvm-17 CI job failures, conditionally define __arena_global variables as 64-bit if __clang_major__ < 18, to make sure .addr_space.1 has no holes. Ideally we should avoid compiling this file using clang-17 at all (arena tests depend on __BPF_FEATURE_ADDR_SPACE_CAST, and are skipped for llvm-17 anyway), but that is a separate topic. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Peilin Ye <yepeilin@google.com> Link: https://lore.kernel.org/r/1b46c6feaf0f1b6984d9ec80e500cc7383e9da1a.1741049567.git.yepeilin@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>

In recent kernels, there are lockdep splats around the struct request_queue::io_lockdep_map, similar to [1], but they typically don't show up until reclaim with writeback happens. Having multiple kernel versions released with a known risc of kernel deadlock during reclaim writeback should IMHO be addressed and backported to -stable with the highest priority. In order to have these lockdep splats show up earlier, preferrably during system initialization, prime the struct request_queue::io_lockdep_map as GFP_KERNEL reclaim- tainted. This will instead lead to lockdep splats looking similar to [2], but without the need for reclaim + writeback happening. [1]: [ 189.762244] ====================================================== [ 189.762432] WARNING: possible circular locking dependency detected [ 189.762441] 6.14.0-rc6-xe+ #6 Tainted: G U [ 189.762450] ------------------------------------------------------ [ 189.762459] kswapd0/119 is trying to acquire lock: [ 189.762467] ffff888110ceb710 (&q->q_usage_counter(io)#26){++++}-{0:0}, at: __submit_bio+0x76/0x230 [ 189.762485] but task is already holding lock: [ 189.762494] ffffffff834c97c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xbe/0xb00 [ 189.762507] which lock already depends on the new lock. [ 189.762519] the existing dependency chain (in reverse order) is: [ 189.762529] -> #2 (fs_reclaim){+.+.}-{0:0}: [ 189.762540] fs_reclaim_acquire+0xc5/0x100 [ 189.762548] kmem_cache_alloc_lru_noprof+0x4a/0x480 [ 189.762558] alloc_inode+0xaa/0xe0 [ 189.762566] iget_locked+0x157/0x330 [ 189.762573] kernfs_get_inode+0x1b/0x110 [ 189.762582] kernfs_get_tree+0x1b0/0x2e0 [ 189.762590] sysfs_get_tree+0x1f/0x60 [ 189.762597] vfs_get_tree+0x2a/0xf0 [ 189.762605] path_mount+0x4cd/0xc00 [ 189.762613] __x64_sys_mount+0x119/0x150 [ 189.762621] x64_sys_call+0x14f2/0x2310 [ 189.762630] do_syscall_64+0x91/0x180 [ 189.762637] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 189.762647] -> #1 (&root->kernfs_rwsem){++++}-{3:3}: [ 189.762659] down_write+0x3e/0xf0 [ 189.762667] kernfs_remove+0x32/0x60 [ 189.762676] sysfs_remove_dir+0x4f/0x60 [ 189.762685] __kobject_del+0x33/0xa0 [ 189.762709] kobject_del+0x13/0x30 [ 189.762716] elv_unregister_queue+0x52/0x80 [ 189.762725] elevator_switch+0x68/0x360 [ 189.762733] elv_iosched_store+0x14b/0x1b0 [ 189.762756] queue_attr_store+0x181/0x1e0 [ 189.762765] sysfs_kf_write+0x49/0x80 [ 189.762773] kernfs_fop_write_iter+0x17d/0x250 [ 189.762781] vfs_write+0x281/0x540 [ 189.762790] ksys_write+0x72/0xf0 [ 189.762798] __x64_sys_write+0x19/0x30 [ 189.762807] x64_sys_call+0x2a3/0x2310 [ 189.762815] do_syscall_64+0x91/0x180 [ 189.762823] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 189.762833] -> #0 (&q->q_usage_counter(io)#26){++++}-{0:0}: [ 189.762845] __lock_acquire+0x1525/0x2760 [ 189.762854] lock_acquire+0xca/0x310 [ 189.762861] blk_mq_submit_bio+0x8a2/0xba0 [ 189.762870] __submit_bio+0x76/0x230 [ 189.762878] submit_bio_noacct_nocheck+0x323/0x430 [ 189.762888] submit_bio_noacct+0x2cc/0x620 [ 189.762896] submit_bio+0x38/0x110 [ 189.762904] __swap_writepage+0xf5/0x380 [ 189.762912] swap_writepage+0x3c7/0x600 [ 189.762920] shmem_writepage+0x3da/0x4f0 [ 189.762929] pageout+0x13f/0x310 [ 189.762937] shrink_folio_list+0x61c/0xf60 [ 189.763261] evict_folios+0x378/0xcd0 [ 189.763584] try_to_shrink_lruvec+0x1b0/0x360 [ 189.763946] shrink_one+0x10e/0x200 [ 189.764266] shrink_node+0xc02/0x1490 [ 189.764586] balance_pgdat+0x563/0xb00 [ 189.764934] kswapd+0x1e8/0x430 [ 189.765249] kthread+0x10b/0x260 [ 189.765559] ret_from_fork+0x44/0x70 [ 189.765889] ret_from_fork_asm+0x1a/0x30 [ 189.766198] other info that might help us debug this: [ 189.767089] Chain exists of: &q->q_usage_counter(io)#26 --> &root->kernfs_rwsem --> fs_reclaim [ 189.767971] Possible unsafe locking scenario: [ 189.768555] CPU0 CPU1 [ 189.768849] ---- ---- [ 189.769136] lock(fs_reclaim); [ 189.769421] lock(&root->kernfs_rwsem); [ 189.769714] lock(fs_reclaim); [ 189.770016] rlock(&q->q_usage_counter(io)#26); [ 189.770305] *** DEADLOCK *** [ 189.771167] 1 lock held by kswapd0/119: [ 189.771453] #0: ffffffff834c97c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xbe/0xb00 [ 189.771770] stack backtrace: [ 189.772351] CPU: 4 UID: 0 PID: 119 Comm: kswapd0 Tainted: G U 6.14.0-rc6-xe+ #6 [ 189.772353] Tainted: [U]=USER [ 189.772354] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023 [ 189.772354] Call Trace: [ 189.772355] <TASK> [ 189.772356] dump_stack_lvl+0x6e/0xa0 [ 189.772359] dump_stack+0x10/0x18 [ 189.772360] print_circular_bug.cold+0x17a/0x1b7 [ 189.772363] check_noncircular+0x13a/0x150 [ 189.772365] ? __pfx_stack_trace_consume_entry+0x10/0x10 [ 189.772368] __lock_acquire+0x1525/0x2760 [ 189.772368] ? ret_from_fork_asm+0x1a/0x30 [ 189.772371] lock_acquire+0xca/0x310 [ 189.772372] ? __submit_bio+0x76/0x230 [ 189.772375] ? lock_release+0xd5/0x2c0 [ 189.772376] blk_mq_submit_bio+0x8a2/0xba0 [ 189.772378] ? __submit_bio+0x76/0x230 [ 189.772380] __submit_bio+0x76/0x230 [ 189.772382] ? trace_hardirqs_on+0x1e/0xe0 [ 189.772384] submit_bio_noacct_nocheck+0x323/0x430 [ 189.772386] ? submit_bio_noacct_nocheck+0x323/0x430 [ 189.772387] ? __might_sleep+0x58/0xa0 [ 189.772390] submit_bio_noacct+0x2cc/0x620 [ 189.772391] ? count_memcg_events+0x68/0x90 [ 189.772393] submit_bio+0x38/0x110 [ 189.772395] __swap_writepage+0xf5/0x380 [ 189.772396] swap_writepage+0x3c7/0x600 [ 189.772397] shmem_writepage+0x3da/0x4f0 [ 189.772401] pageout+0x13f/0x310 [ 189.772406] shrink_folio_list+0x61c/0xf60 [ 189.772409] ? isolate_folios+0xe80/0x16b0 [ 189.772410] ? mark_held_locks+0x46/0x90 [ 189.772412] evict_folios+0x378/0xcd0 [ 189.772414] ? evict_folios+0x34a/0xcd0 [ 189.772415] ? lock_is_held_type+0xa3/0x130 [ 189.772417] try_to_shrink_lruvec+0x1b0/0x360 [ 189.772420] shrink_one+0x10e/0x200 [ 189.772421] shrink_node+0xc02/0x1490 [ 189.772423] ? shrink_node+0xa08/0x1490 [ 189.772424] ? shrink_node+0xbd8/0x1490 [ 189.772425] ? mem_cgroup_iter+0x366/0x480 [ 189.772427] balance_pgdat+0x563/0xb00 [ 189.772428] ? balance_pgdat+0x563/0xb00 [ 189.772430] ? trace_hardirqs_on+0x1e/0xe0 [ 189.772431] ? finish_task_switch.isra.0+0xcb/0x330 [ 189.772433] ? __switch_to_asm+0x33/0x70 [ 189.772437] kswapd+0x1e8/0x430 [ 189.772438] ? __pfx_autoremove_wake_function+0x10/0x10 [ 189.772440] ? __pfx_kswapd+0x10/0x10 [ 189.772441] kthread+0x10b/0x260 [ 189.772443] ? __pfx_kthread+0x10/0x10 [ 189.772444] ret_from_fork+0x44/0x70 [ 189.772446] ? __pfx_kthread+0x10/0x10 [ 189.772447] ret_from_fork_asm+0x1a/0x30 [ 189.772450] </TASK> [2]: [ 8.760253] ====================================================== [ 8.760254] WARNING: possible circular locking dependency detected [ 8.760255] 6.14.0-rc6-xe+ #7 Tainted: G U [ 8.760256] ------------------------------------------------------ [ 8.760257] (udev-worker)/674 is trying to acquire lock: [ 8.760259] ffff888100e39148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_remove+0x32/0x60 [ 8.760265] but task is already holding lock: [ 8.760266] ffff888110dc7680 (&q->q_usage_counter(io)#27){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x12/0x30 [ 8.760272] which lock already depends on the new lock. [ 8.760272] the existing dependency chain (in reverse order) is: [ 8.760273] -> #2 (&q->q_usage_counter(io)#27){++++}-{0:0}: [ 8.760276] blk_alloc_queue+0x30a/0x350 [ 8.760279] blk_mq_alloc_queue+0x6b/0xe0 [ 8.760281] scsi_alloc_sdev+0x276/0x3c0 [ 8.760284] scsi_probe_and_add_lun+0x22a/0x440 [ 8.760286] __scsi_scan_target+0x109/0x230 [ 8.760288] scsi_scan_channel+0x65/0xc0 [ 8.760290] scsi_scan_host_selected+0xff/0x140 [ 8.760292] do_scsi_scan_host+0xa7/0xc0 [ 8.760293] do_scan_async+0x1c/0x160 [ 8.760295] async_run_entry_fn+0x32/0x150 [ 8.760299] process_one_work+0x224/0x5f0 [ 8.760302] worker_thread+0x1d4/0x3e0 [ 8.760304] kthread+0x10b/0x260 [ 8.760306] ret_from_fork+0x44/0x70 [ 8.760309] ret_from_fork_asm+0x1a/0x30 [ 8.760312] -> #1 (fs_reclaim){+.+.}-{0:0}: [ 8.760315] fs_reclaim_acquire+0xc5/0x100 [ 8.760317] kmem_cache_alloc_lru_noprof+0x4a/0x480 [ 8.760319] alloc_inode+0xaa/0xe0 [ 8.760322] iget_locked+0x157/0x330 [ 8.760323] kernfs_get_inode+0x1b/0x110 [ 8.760325] kernfs_get_tree+0x1b0/0x2e0 [ 8.760327] sysfs_get_tree+0x1f/0x60 [ 8.760329] vfs_get_tree+0x2a/0xf0 [ 8.760332] path_mount+0x4cd/0xc00 [ 8.760334] __x64_sys_mount+0x119/0x150 [ 8.760336] x64_sys_call+0x14f2/0x2310 [ 8.760338] do_syscall_64+0x91/0x180 [ 8.760340] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 8.760342] -> #0 (&root->kernfs_rwsem){++++}-{3:3}: [ 8.760345] __lock_acquire+0x1525/0x2760 [ 8.760347] lock_acquire+0xca/0x310 [ 8.760348] down_write+0x3e/0xf0 [ 8.760350] kernfs_remove+0x32/0x60 [ 8.760351] sysfs_remove_dir+0x4f/0x60 [ 8.760353] __kobject_del+0x33/0xa0 [ 8.760355] kobject_del+0x13/0x30 [ 8.760356] elv_unregister_queue+0x52/0x80 [ 8.760358] elevator_switch+0x68/0x360 [ 8.760360] elv_iosched_store+0x14b/0x1b0 [ 8.760362] queue_attr_store+0x181/0x1e0 [ 8.760364] sysfs_kf_write+0x49/0x80 [ 8.760366] kernfs_fop_write_iter+0x17d/0x250 [ 8.760367] vfs_write+0x281/0x540 [ 8.760370] ksys_write+0x72/0xf0 [ 8.760372] __x64_sys_write+0x19/0x30 [ 8.760374] x64_sys_call+0x2a3/0x2310 [ 8.760376] do_syscall_64+0x91/0x180 [ 8.760377] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 8.760380] other info that might help us debug this: [ 8.760380] Chain exists of: &root->kernfs_rwsem --> fs_reclaim --> &q->q_usage_counter(io)#27 [ 8.760384] Possible unsafe locking scenario: [ 8.760384] CPU0 CPU1 [ 8.760385] ---- ---- [ 8.760385] lock(&q->q_usage_counter(io)#27); [ 8.760387] lock(fs_reclaim); [ 8.760388] lock(&q->q_usage_counter(io)#27); [ 8.760390] lock(&root->kernfs_rwsem); [ 8.760391] *** DEADLOCK *** [ 8.760391] 6 locks held by (udev-worker)/674: [ 8.760392] #0: ffff8881209ac420 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0x72/0xf0 [ 8.760398] #1: ffff88810c80f488 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x136/0x250 [ 8.760402] #2: ffff888125d1d330 (kn->active#101){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x13f/0x250 [ 8.760406] #3: ffff888110dc7bb0 (&q->sysfs_lock){+.+.}-{3:3}, at: queue_attr_store+0x148/0x1e0 [ 8.760411] #4: ffff888110dc7680 (&q->q_usage_counter(io)#27){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x12/0x30 [ 8.760416] #5: ffff888110dc76b8 (&q->q_usage_counter(queue)#27){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x12/0x30 [ 8.760421] stack backtrace: [ 8.760422] CPU: 7 UID: 0 PID: 674 Comm: (udev-worker) Tainted: G U 6.14.0-rc6-xe+ #7 [ 8.760424] Tainted: [U]=USER [ 8.760425] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023 [ 8.760426] Call Trace: [ 8.760427] <TASK> [ 8.760428] dump_stack_lvl+0x6e/0xa0 [ 8.760431] dump_stack+0x10/0x18 [ 8.760433] print_circular_bug.cold+0x17a/0x1b7 [ 8.760437] check_noncircular+0x13a/0x150 [ 8.760441] ? save_trace+0x54/0x360 [ 8.760445] __lock_acquire+0x1525/0x2760 [ 8.760446] ? irqentry_exit+0x3a/0xb0 [ 8.760448] ? sysvec_apic_timer_interrupt+0x57/0xc0 [ 8.760452] lock_acquire+0xca/0x310 [ 8.760453] ? kernfs_remove+0x32/0x60 [ 8.760457] down_write+0x3e/0xf0 [ 8.760459] ? kernfs_remove+0x32/0x60 [ 8.760460] kernfs_remove+0x32/0x60 [ 8.760462] sysfs_remove_dir+0x4f/0x60 [ 8.760464] __kobject_del+0x33/0xa0 [ 8.760466] kobject_del+0x13/0x30 [ 8.760467] elv_unregister_queue+0x52/0x80 [ 8.760470] elevator_switch+0x68/0x360 [ 8.760472] elv_iosched_store+0x14b/0x1b0 [ 8.760475] queue_attr_store+0x181/0x1e0 [ 8.760479] ? lock_acquire+0xca/0x310 [ 8.760480] ? kernfs_fop_write_iter+0x13f/0x250 [ 8.760482] ? lock_is_held_type+0xa3/0x130 [ 8.760485] sysfs_kf_write+0x49/0x80 [ 8.760487] kernfs_fop_write_iter+0x17d/0x250 [ 8.760489] vfs_write+0x281/0x540 [ 8.760494] ksys_write+0x72/0xf0 [ 8.760497] __x64_sys_write+0x19/0x30 [ 8.760499] x64_sys_call+0x2a3/0x2310 [ 8.760502] do_syscall_64+0x91/0x180 [ 8.760504] ? trace_hardirqs_off+0x5d/0xe0 [ 8.760506] ? handle_softirqs+0x479/0x4d0 [ 8.760508] ? hrtimer_interrupt+0x13f/0x280 [ 8.760511] ? irqentry_exit_to_user_mode+0x8b/0x260 [ 8.760513] ? clear_bhb_loop+0x15/0x70 [ 8.760515] ? clear_bhb_loop+0x15/0x70 [ 8.760516] ? clear_bhb_loop+0x15/0x70 [ 8.760518] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 8.760520] RIP: 0033:0x7aa3bf2f5504 [ 8.760522] Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d c5 8b 10 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 [ 8.760523] RSP: 002b:00007ffc1e3697d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 [ 8.760526] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007aa3bf2f5504 [ 8.760527] RDX: 0000000000000003 RSI: 00007ffc1e369ae0 RDI: 000000000000001c [ 8.760528] RBP: 00007ffc1e369800 R08: 00007aa3bf3f51c8 R09: 00007ffc1e3698b0 [ 8.760528] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 [ 8.760529] R13: 00007ffc1e369ae0 R14: 0000613ccf21f2f0 R15: 00007aa3bf3f4e80 [ 8.760533] </TASK> v2: - Update a code comment to increase readability (Ming Lei). Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20250318095548.5187-1-thomas.hellstrom@linux.intel.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

perf test 11 hwmon fails on s390 with this error # ./perf test -Fv 11 --- start --- ---- end ---- 11.1: Basic parsing test : Ok --- start --- Testing 'temp_test_hwmon_event1' Using CPUID IBM,3931,704,A01,3.7,002f temp_test_hwmon_event1 -> hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/ FAILED tests/hwmon_pmu.c:189 Unexpected config for 'temp_test_hwmon_event1', 292470092988416 != 655361 ---- end ---- 11.2: Parsing without PMU name : FAILED! --- start --- Testing 'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/' FAILED tests/hwmon_pmu.c:189 Unexpected config for 'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/', 292470092988416 != 655361 ---- end ---- 11.3: Parsing with PMU name : FAILED! # The root cause is in member test_event::config which is initialized to 0xA0001 or 655361. During event parsing a long list event parsing functions are called and end up with this gdb call stack: #0 hwmon_pmu__config_term (hwm=0x168dfd0, attr=0x3ffffff5ee8, term=0x168db60, err=0x3ffffff81c8) at util/hwmon_pmu.c:623 #1 hwmon_pmu__config_terms (pmu=0x168dfd0, attr=0x3ffffff5ee8, terms=0x3ffffff5ea8, err=0x3ffffff81c8) at util/hwmon_pmu.c:662 #2 0x00000000012f870c in perf_pmu__config_terms (pmu=0x168dfd0, attr=0x3ffffff5ee8, terms=0x3ffffff5ea8, zero=false, apply_hardcoded=false, err=0x3ffffff81c8) at util/pmu.c:1519 #3 0x00000000012f88a4 in perf_pmu__config (pmu=0x168dfd0, attr=0x3ffffff5ee8, head_terms=0x3ffffff5ea8, apply_hardcoded=false, err=0x3ffffff81c8) at util/pmu.c:1545 #4 0x00000000012680c4 in parse_events_add_pmu (parse_state=0x3ffffff7fb8, list=0x168dc00, pmu=0x168dfd0, const_parsed_terms=0x3ffffff6090, auto_merge_stats=true, alternate_hw_config=10) at util/parse-events.c:1508 #5 0x00000000012684c6 in parse_events_multi_pmu_add (parse_state=0x3ffffff7fb8, event_name=0x168ec10 "temp_test_hwmon_event1", hw_config=10, const_parsed_terms=0x0, listp=0x3ffffff6230, loc_=0x3ffffff70e0) at util/parse-events.c:1592 #6 0x00000000012f0e4e in parse_events_parse (_parse_state=0x3ffffff7fb8, scanner=0x16878c0) at util/parse-events.y:293 #7 0x00000000012695a0 in parse_events__scanner (str=0x3ffffff81d8 "temp_test_hwmon_event1", input=0x0, parse_state=0x3ffffff7fb8) at util/parse-events.c:1867 #8 0x000000000126a1e8 in __parse_events (evlist=0x168b580, str=0x3ffffff81d8 "temp_test_hwmon_event1", pmu_filter=0x0, err=0x3ffffff81c8, fake_pmu=false, warn_if_reordered=true, fake_tp=false) at util/parse-events.c:2136 #9 0x00000000011e36aa in parse_events (evlist=0x168b580, str=0x3ffffff81d8 "temp_test_hwmon_event1", err=0x3ffffff81c8) at /root/linux/tools/perf/util/parse-events.h:41 #10 0x00000000011e3e64 in do_test (i=0, with_pmu=false, with_alias=false) at tests/hwmon_pmu.c:164 #11 0x00000000011e422c in test__hwmon_pmu (with_pmu=false) at tests/hwmon_pmu.c:219 #12 0x00000000011e431c in test__hwmon_pmu_without_pmu (test=0x1610368 <suite.hwmon_pmu>, subtest=1) at tests/hwmon_pmu.c:23 where the attr::config is set to value 292470092988416 or 0x10a0000000000 in line 625 of file ./util/hwmon_pmu.c: attr->config = key.type_and_num; However member key::type_and_num is defined as union and bit field: union hwmon_pmu_event_key { long type_and_num; struct { int num :16; enum hwmon_type type :8; }; }; s390 is big endian and Intel is little endian architecture. The events for the hwmon dummy pmu have num = 1 or num = 2 and type is set to HWMON_TYPE_TEMP (which is 10). On s390 this assignes member key::type_and_num the value of 0x10a0000000000 (which is 292470092988416) as shown in above trace output. Fix this and export the structure/union hwmon_pmu_event_key so the test shares the same implementation as the event parsing functions for union and bit fields. This should avoid endianess issues on all platforms. Output after: # ./perf test -F 11 11.1: Basic parsing test : Ok 11.2: Parsing without PMU name : Ok 11.3: Parsing with PMU name : Ok # Fixes: 531ee0f ("perf test: Add hwmon "PMU" test") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250131112400.568975-1-tmricht@linux.ibm.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Ian told me that there are many memory leaks in the hierarchy mode. I can easily reproduce it with the follwing command. $ make DEBUG=1 EXTRA_CFLAGS=-fsanitize=leak $ perf record --latency -g -- ./perf test -w thloop $ perf report -H --stdio ... Indirect leak of 168 byte(s) in 21 object(s) allocated from: #0 0x7f3414c16c65 in malloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:75 #1 0x55ed3602346e in map__get util/map.h:189 #2 0x55ed36024cc4 in hist_entry__init util/hist.c:476 #3 0x55ed36025208 in hist_entry__new util/hist.c:588 #4 0x55ed36027c05 in hierarchy_insert_entry util/hist.c:1587 #5 0x55ed36027e2e in hists__hierarchy_insert_entry util/hist.c:1638 #6 0x55ed36027fa4 in hists__collapse_insert_entry util/hist.c:1685 #7 0x55ed360283e8 in hists__collapse_resort util/hist.c:1776 #8 0x55ed35de0323 in report__collapse_hists /home/namhyung/project/linux/tools/perf/builtin-report.c:735 #9 0x55ed35de15b4 in __cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1119 #10 0x55ed35de43dc in cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1867 #11 0x55ed35e66767 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:351 #12 0x55ed35e66a0e in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:404 #13 0x55ed35e66b67 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:448 #14 0x55ed35e66eb0 in main /home/namhyung/project/linux/tools/perf/perf.c:556 #15 0x7f340ac33d67 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 ... $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak' 93 I found that hist_entry__delete() missed to release child entries in the hierarchy tree (hroot_{in,out}). It needs to iterate the child entries and call hist_entry__delete() recursively. After this change: $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak' 0 Reported-by: Ian Rogers <irogers@google.com> Tested-by Thomas Falcon <thomas.falcon@intel.com> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250307061250.320849-2-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>

The env.pmu_mapping can be leaked when it reads data from a pipe on AMD. For a pipe data, it reads the header data including pmu_mapping from PERF_RECORD_HEADER_FEATURE runtime. But it's already set in: perf_session__new() __perf_session__new() evlist__init_trace_event_sample_raw() evlist__has_amd_ibs() perf_env__nr_pmu_mappings() Then it'll overwrite that when it processes the HEADER_FEATURE record. Here's a report from address sanitizer. Direct leak of 2689 byte(s) in 1 object(s) allocated from: #0 0x7fed8f814596 in realloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:98 #1 0x5595a7d416b1 in strbuf_grow util/strbuf.c:64 #2 0x5595a7d414ef in strbuf_init util/strbuf.c:25 #3 0x5595a7d0f4b7 in perf_env__read_pmu_mappings util/env.c:362 #4 0x5595a7d12ab7 in perf_env__nr_pmu_mappings util/env.c:517 #5 0x5595a7d89d2f in evlist__has_amd_ibs util/amd-sample-raw.c:315 #6 0x5595a7d87fb2 in evlist__init_trace_event_sample_raw util/sample-raw.c:23 #7 0x5595a7d7f893 in __perf_session__new util/session.c:179 #8 0x5595a7b79572 in perf_session__new util/session.h:115 #9 0x5595a7b7e9dc in cmd_report builtin-report.c:1603 #10 0x5595a7c019eb in run_builtin perf.c:351 #11 0x5595a7c01c92 in handle_internal_command perf.c:404 #12 0x5595a7c01deb in run_argv perf.c:448 #13 0x5595a7c02134 in main perf.c:556 #14 0x7fed85833d67 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 Let's free the existing pmu_mapping data if any. Cc: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250311000416.817631-1-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>

When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush() generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC, which causes the flush_bio to be throttled by wbt_wait(). An example from v5.4, similar problem also exists in upstream: crash> bt 2091206 PID: 2091206 TASK: ffff2050df92a300 CPU: 109 COMMAND: "kworker/u260:0" #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8 #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4 #2 [ffff800084a2f880] schedule at ffff800040bfa4b4 #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4 #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0 #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254 #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38 #8 [ffff800084a2fa60] generic_make_request at ffff800040570138 #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4 #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs] #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs] #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs] #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs] #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs] #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs] #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08 #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc #18 [ffff800084a2fe70] kthread at ffff800040118de4 After commit 2def284 ("xfs: don't allow log IO to be throttled"), the metadata submitted by xlog_write_iclog() should not be throttled. But due to the existence of the dm layer, throttling flush_bio indirectly causes the metadata bio to be throttled. Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes wbt_should_throttle() return false to avoid wbt_wait(). Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com> Reviewed-by: Tianxiang Peng <txpeng@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

v2: - Created a single error handling unlock and exit in veth_pool_store - Greatly expanded commit message with previous explanatory-only text Summary: Use rtnl_mutex to synchronize veth_pool_store with itself, ibmveth_close and ibmveth_open, preventing multiple calls in a row to napi_disable. Background: Two (or more) threads could call veth_pool_store through writing to /sys/devices/vio/30000002/pool*/*. You can do this easily with a little shell script. This causes a hang. I configured LOCKDEP, compiled ibmveth.c with DEBUG, and built a new kernel. I ran this test again and saw: Setting pool0/active to 0 Setting pool1/active to 1 [ 73.911067][ T4365] ibmveth 30000002 eth0: close starting Setting pool1/active to 1 Setting pool1/active to 0 [ 73.911367][ T4366] ibmveth 30000002 eth0: close starting [ 73.916056][ T4365] ibmveth 30000002 eth0: close complete [ 73.916064][ T4365] ibmveth 30000002 eth0: open starting [ 110.808564][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 230.808495][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 243.683786][ T123] INFO: task stress.sh:4365 blocked for more than 122 seconds. [ 243.683827][ T123] Not tainted 6.14.0-01103-g2df0c02dab82-dirty #8 [ 243.683833][ T123] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 243.683838][ T123] task:stress.sh state:D stack:28096 pid:4365 tgid:4365 ppid:4364 task_flags:0x400040 flags:0x00042000 [ 243.683852][ T123] Call Trace: [ 243.683857][ T123] [c00000000c38f690] [0000000000000001] 0x1 (unreliable) [ 243.683868][ T123] [c00000000c38f840] [c00000000001f908] __switch_to+0x318/0x4e0 [ 243.683878][ T123] [c00000000c38f8a0] [c000000001549a70] __schedule+0x500/0x12a0 [ 243.683888][ T123] [c00000000c38f9a0] [c00000000154a878] schedule+0x68/0x210 [ 243.683896][ T123] [c00000000c38f9d0] [c00000000154ac80] schedule_preempt_disabled+0x30/0x50 [ 243.683904][ T123] [c00000000c38fa00] [c00000000154dbb0] __mutex_lock+0x730/0x10f0 [ 243.683913][ T123] [c00000000c38fb10] [c000000001154d40] napi_enable+0x30/0x60 [ 243.683921][ T123] [c00000000c38fb40] [c000000000f4ae94] ibmveth_open+0x68/0x5dc [ 243.683928][ T123] [c00000000c38fbe0] [c000000000f4aa20] veth_pool_store+0x220/0x270 [ 243.683936][ T123] [c00000000c38fc70] [c000000000826278] sysfs_kf_write+0x68/0xb0 [ 243.683944][ T123] [c00000000c38fcb0] [c0000000008240b8] kernfs_fop_write_iter+0x198/0x2d0 [ 243.683951][ T123] [c00000000c38fd00] [c00000000071b9ac] vfs_write+0x34c/0x650 [ 243.683958][ T123] [c00000000c38fdc0] [c00000000071bea8] ksys_write+0x88/0x150 [ 243.683966][ T123] [c00000000c38fe10] [c0000000000317f4] system_call_exception+0x124/0x340 [ 243.683973][ T123] [c00000000c38fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec ... [ 243.684087][ T123] Showing all locks held in the system: [ 243.684095][ T123] 1 lock held by khungtaskd/123: [ 243.684099][ T123] #0: c00000000278e370 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x50/0x248 [ 243.684114][ T123] 4 locks held by stress.sh/4365: [ 243.684119][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684132][ T123] #1: c000000041aea888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684143][ T123] #2: c0000000366fb9a8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684155][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_enable+0x30/0x60 [ 243.684166][ T123] 5 locks held by stress.sh/4366: [ 243.684170][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684183][ T123] #1: c00000000aee2288 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684194][ T123] #2: c0000000366f4ba8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684205][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_disable+0x30/0x60 [ 243.684216][ T123] #4: c0000003ff9bbf18 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x138/0x12a0 From the ibmveth debug, two threads are calling veth_pool_store, which calls ibmveth_close and ibmveth_open. Here's the sequence: T4365 T4366 ----------------- ----------------- --------- veth_pool_store veth_pool_store ibmveth_close ibmveth_close napi_disable napi_disable ibmveth_open napi_enable <- HANG ibmveth_close calls napi_disable at the top and ibmveth_open calls napi_enable at the top. https://docs.kernel.org/networking/napi.html]] says The control APIs are not idempotent. Control API calls are safe against concurrent use of datapath APIs but an incorrect sequence of control API calls may result in crashes, deadlocks, or race conditions. For example, calling napi_disable() multiple times in a row will deadlock. In the normal open and close paths, rtnl_mutex is acquired to prevent other callers. This is missing from veth_pool_store. Use rtnl_mutex in veth_pool_store fixes these hangs. Signed-off-by: Dave Marquardt <davemarq@linux.ibm.com> Fixes: 860f242 ("[PATCH] ibmveth change buffer pools dynamically") Reviewed-by: Nick Child <nnac123@linux.ibm.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250402154403.386744-1-davemarq@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

There is a potential deadlock if we do report zones in an IO context, detailed in below lockdep report. When one process do a report zones and another process freezes the block device, the report zones side cannot allocate a tag because the freeze is already started. This can thus result in new block group creation to hang forever, blocking the write path. Thankfully, a new block group should be created on empty zones. So, reporting the zones is not necessary and we can set the write pointer = 0 and load the zone capacity from the block layer using bdev_zone_capacity() helper. ====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc1 torvalds#252 Not tainted ------------------------------------------------------ modprobe/1110 is trying to acquire lock: ffff888100ac83e0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0x38f/0xb60 but task is already holding lock: ffff8881205b6f20 (&q->q_usage_counter(queue)#16){++++}-{0:0}, at: sd_remove+0x85/0x130 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&q->q_usage_counter(queue)#16){++++}-{0:0}: blk_queue_enter+0x3d9/0x500 blk_mq_alloc_request+0x47d/0x8e0 scsi_execute_cmd+0x14f/0xb80 sd_zbc_do_report_zones+0x1c1/0x470 sd_zbc_report_zones+0x362/0xd60 blkdev_report_zones+0x1b1/0x2e0 btrfs_get_dev_zones+0x215/0x7e0 [btrfs] btrfs_load_block_group_zone_info+0x6d2/0x2c10 [btrfs] btrfs_make_block_group+0x36b/0x870 [btrfs] btrfs_create_chunk+0x147d/0x2320 [btrfs] btrfs_chunk_alloc+0x2ce/0xcf0 [btrfs] start_transaction+0xce6/0x1620 [btrfs] btrfs_uuid_scan_kthread+0x4ee/0x5b0 [btrfs] kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #2 (&fs_info->dev_replace.rwsem){++++}-{4:4}: down_read+0x9b/0x470 btrfs_map_block+0x2ce/0x2ce0 [btrfs] btrfs_submit_chunk+0x2d4/0x16c0 [btrfs] btrfs_submit_bbio+0x16/0x30 [btrfs] btree_write_cache_pages+0xb5a/0xf90 [btrfs] do_writepages+0x17f/0x7b0 __writeback_single_inode+0x114/0xb00 writeback_sb_inodes+0x52b/0xe00 wb_writeback+0x1a7/0x800 wb_workfn+0x12a/0xbd0 process_one_work+0x85a/0x1460 worker_thread+0x5e2/0xfc0 kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #1 (&fs_info->zoned_meta_io_lock){+.+.}-{4:4}: __mutex_lock+0x1aa/0x1360 btree_write_cache_pages+0x252/0xf90 [btrfs] do_writepages+0x17f/0x7b0 __writeback_single_inode+0x114/0xb00 writeback_sb_inodes+0x52b/0xe00 wb_writeback+0x1a7/0x800 wb_workfn+0x12a/0xbd0 process_one_work+0x85a/0x1460 worker_thread+0x5e2/0xfc0 kthread+0x39d/0x750 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 -> #0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}: __lock_acquire+0x2f52/0x5ea0 lock_acquire+0x1b1/0x540 __flush_work+0x3ac/0xb60 wb_shutdown+0x15b/0x1f0 bdi_unregister+0x172/0x5b0 del_gendisk+0x841/0xa20 sd_remove+0x85/0x130 device_release_driver_internal+0x368/0x520 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 __scsi_remove_device+0x272/0x340 scsi_forget_host+0xf7/0x170 scsi_remove_host+0xd2/0x2a0 sdebug_driver_remove+0x52/0x2f0 [scsi_debug] device_release_driver_internal+0x368/0x520 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 device_unregister+0x13/0xa0 sdebug_do_remove_host+0x1fb/0x290 [scsi_debug] scsi_debug_exit+0x17/0x70 [scsi_debug] __do_sys_delete_module.isra.0+0x321/0x520 do_syscall_64+0x93/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: (work_completion)(&(&wb->dwork)->work) --> &fs_info->dev_replace.rwsem --> &q->q_usage_counter(queue)#16 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->q_usage_counter(queue)#16); lock(&fs_info->dev_replace.rwsem); lock(&q->q_usage_counter(queue)#16); lock((work_completion)(&(&wb->dwork)->work)); *** DEADLOCK *** 5 locks held by modprobe/1110: #0: ffff88811f7bc108 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520 #1: ffff8881022ee0e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x20/0x2a0 #2: ffff88811b4c4378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520 #3: ffff8881205b6f20 (&q->q_usage_counter(queue)#16){++++}-{0:0}, at: sd_remove+0x85/0x130 #4: ffffffffa3284360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xda/0xb60 stack backtrace: CPU: 0 UID: 0 PID: 1110 Comm: modprobe Not tainted 6.14.0-rc1 torvalds#252 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6a/0x90 print_circular_bug.cold+0x1e0/0x274 check_noncircular+0x306/0x3f0 ? __pfx_check_noncircular+0x10/0x10 ? mark_lock+0xf5/0x1650 ? __pfx_check_irq_usage+0x10/0x10 ? lockdep_lock+0xca/0x1c0 ? __pfx_lockdep_lock+0x10/0x10 __lock_acquire+0x2f52/0x5ea0 ? __pfx___lock_acquire+0x10/0x10 ? __pfx_mark_lock+0x10/0x10 lock_acquire+0x1b1/0x540 ? __flush_work+0x38f/0xb60 ? __pfx_lock_acquire+0x10/0x10 ? __pfx_lock_release+0x10/0x10 ? mark_held_locks+0x94/0xe0 ? __flush_work+0x38f/0xb60 __flush_work+0x3ac/0xb60 ? __flush_work+0x38f/0xb60 ? __pfx_mark_lock+0x10/0x10 ? __pfx___flush_work+0x10/0x10 ? __pfx_wq_barrier_func+0x10/0x10 ? __pfx___might_resched+0x10/0x10 ? mark_held_locks+0x94/0xe0 wb_shutdown+0x15b/0x1f0 bdi_unregister+0x172/0x5b0 ? __pfx_bdi_unregister+0x10/0x10 ? up_write+0x1ba/0x510 del_gendisk+0x841/0xa20 ? __pfx_del_gendisk+0x10/0x10 ? _raw_spin_unlock_irqrestore+0x35/0x60 ? __pm_runtime_resume+0x79/0x110 sd_remove+0x85/0x130 device_release_driver_internal+0x368/0x520 ? kobject_put+0x5d/0x4a0 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 ? __pfx_device_del+0x10/0x10 __scsi_remove_device+0x272/0x340 scsi_forget_host+0xf7/0x170 scsi_remove_host+0xd2/0x2a0 sdebug_driver_remove+0x52/0x2f0 [scsi_debug] ? kernfs_remove_by_name_ns+0xc0/0xf0 device_release_driver_internal+0x368/0x520 ? kobject_put+0x5d/0x4a0 bus_remove_device+0x1f1/0x3f0 device_del+0x3bd/0x9c0 ? __pfx_device_del+0x10/0x10 ? __pfx___mutex_unlock_slowpath+0x10/0x10 device_unregister+0x13/0xa0 sdebug_do_remove_host+0x1fb/0x290 [scsi_debug] scsi_debug_exit+0x17/0x70 [scsi_debug] __do_sys_delete_module.isra.0+0x321/0x520 ? __pfx___do_sys_delete_module.isra.0+0x10/0x10 ? __pfx_slab_free_after_rcu_debug+0x10/0x10 ? kasan_save_stack+0x2c/0x50 ? kasan_record_aux_stack+0xa3/0xb0 ? __call_rcu_common.constprop.0+0xc4/0xfb0 ? kmem_cache_free+0x3a0/0x590 ? __x64_sys_close+0x78/0xd0 do_syscall_64+0x93/0x180 ? lock_is_held_type+0xd5/0x130 ? __call_rcu_common.constprop.0+0x3c0/0xfb0 ? lockdep_hardirqs_on+0x78/0x100 ? __call_rcu_common.constprop.0+0x3c0/0xfb0 ? __pfx___call_rcu_common.constprop.0+0x10/0x10 ? kmem_cache_free+0x3a0/0x590 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? __pfx___x64_sys_openat+0x10/0x10 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f436712b68b RSP: 002b:00007ffe9f1a8658 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 00005559b367fd80 RCX: 00007f436712b68b RDX: 0000000000000000 RSI: 0000000000000800 RDI: 00005559b367fde8 RBP: 00007ffe9f1a8680 R08: 1999999999999999 R09: 0000000000000000 R10: 00007f43671a5fe0 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffe9f1a86b0 R14: 0000000000000000 R15: 0000000000000000 </TASK> Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> CC: <stable@vger.kernel.org> # 6.13+ Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>

When migrating a THP, concurrent access to the PMD migration entry during a deferred split scan can lead to an invalid address access, as illustrated below. To prevent this invalid access, it is necessary to check the PMD migration entry and return early. In this context, there is no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the equality of the target folio. Since the PMD migration entry is locked, it cannot be served as the target. Mailing list discussion and explanation from Hugh Dickins: "An anon_vma lookup points to a location which may contain the folio of interest, but might instead contain another folio: and weeding out those other folios is precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of replacing the wrong folio" comment a few lines above it) is for." BUG: unable to handle page fault for address: ffffea60001db008 CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60 Call Trace: <TASK> try_to_migrate_one+0x28c/0x3730 rmap_walk_anon+0x4f6/0x770 unmap_folio+0x196/0x1f0 split_huge_page_to_list_to_order+0x9f6/0x1560 deferred_split_scan+0xac5/0x12a0 shrinker_debugfs_scan_write+0x376/0x470 full_proxy_write+0x15c/0x220 vfs_write+0x2fc/0xcb0 ksys_write+0x146/0x250 do_syscall_64+0x6a/0x120 entry_SYSCALL_64_after_hwframe+0x76/0x7e The bug is found by syzkaller on an internal kernel, then confirmed on upstream. Link: https://lkml.kernel.org/r/20250421113536.3682201-1-gavinguo@igalia.com Link: https://lore.kernel.org/all/20250414072737.1698513-1-gavinguo@igalia.com/ Link: https://lore.kernel.org/all/20250418085802.2973519-1-gavinguo@igalia.com/ Fixes: 84c3fc4 ("mm: thp: check pmd migration entry in common path") Signed-off-by: Gavin Guo <gavinguo@igalia.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Acked-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Cc: Florent Revest <revest@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

If we finds a vq without a name in our input array in virtio_ccw_find_vqs(), we treat it as "non-existing" and set the vq pointer to NULL; we will not call virtio_ccw_setup_vq() to allocate/setup a vq. Consequently, we create only a queue if it actually exists (name != NULL) and assign an incremental queue index to each such existing queue. However, in virtio_ccw_register_adapter_ind()->get_airq_indicator() we will not ignore these "non-existing queues", but instead assign an airq indicator to them. Besides never releasing them in virtio_ccw_drop_indicators() (because there is no virtqueue), the bigger issue seems to be that there will be a disagreement between the device and the Linux guest about the airq indicator to be used for notifying a queue, because the indicator bit for adapter I/O interrupt is derived from the queue index. The virtio spec states under "Setting Up Two-Stage Queue Indicators": ... indicator contains the guest address of an area wherein the indicators for the devices are contained, starting at bit_nr, one bit per virtqueue of the device. And further in "Notification via Adapter I/O Interrupts": For notifying the driver of virtqueue buffers, the device sets the bit in the guest-provided indicator area at the corresponding offset. For example, QEMU uses in virtio_ccw_notify() the queue index (passed as "vector") to select the relevant indicator bit. If a queue does not exist, it does not have a corresponding indicator bit assigned, because it effectively doesn't have a queue index. Using a virtio-balloon-ccw device under QEMU with free-page-hinting disabled ("free-page-hint=off") but free-page-reporting enabled ("free-page-reporting=on") will result in free page reporting not working as expected: in the virtio_balloon driver, we'll be stuck forever in virtballoon_free_page_report()->wait_event(), because the waitqueue will not be woken up as the notification from the device is lost: it would use the wrong indicator bit. Free page reporting stops working and we get splats (when configured to detect hung wqs) like: INFO: task kworker/1:3:463 blocked for more than 61 seconds. Not tainted 6.14.0 #4 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:3 [...] Workqueue: events page_reporting_process Call Trace: [<000002f404e6dfb2>] __schedule+0x402/0x1640 [<000002f404e6f22e>] schedule+0x3e/0xe0 [<000002f3846a88fa>] virtballoon_free_page_report+0xaa/0x110 [virtio_balloon] [<000002f40435c8a4>] page_reporting_process+0x2e4/0x740 [<000002f403fd3ee2>] process_one_work+0x1c2/0x400 [<000002f403fd4b96>] worker_thread+0x296/0x420 [<000002f403fe10b4>] kthread+0x124/0x290 [<000002f403f4e0dc>] __ret_from_fork+0x3c/0x60 [<000002f404e77272>] ret_from_fork+0xa/0x38 There was recently a discussion [1] whether the "holes" should be treated differently again, effectively assigning also non-existing queues a queue index: that should also fix the issue, but requires other workarounds to not break existing setups. Let's fix it without affecting existing setups for now by properly ignoring the non-existing queues, so the indicator bits will match the queue indexes. [1] https://lore.kernel.org/all/cover.1720611677.git.mst@redhat.com/ Fixes: a229989 ("virtio: don't allocate vqs when names[i] = NULL") Reported-by: Chandra Merla <cmerla@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: David Hildenbrand <david@redhat.com> Tested-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20250402203621.940090-1-david@redhat.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

As shown in [1], it is possible to corrupt a BPF ELF file such that arbitrary BPF instructions are loaded by libbpf. This can be done by setting a symbol (BPF program) section offset to a large (unsigned) number such that <section start + symbol offset> overflows and points before the section data in the memory. Consider the situation below where: - prog_start = sec_start + symbol_offset <-- size_t overflow here - prog_end = prog_start + prog_size prog_start sec_start prog_end sec_end | | | | v v v v .....................|################################|............ The report in [1] also provides a corrupted BPF ELF which can be used as a reproducer: $ readelf -S crash Section Headers: [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [ 2] uretprobe.mu[...] PROGBITS 0000000000000000 00000040 0000000000000068 0000000000000000 AX 0 0 8 $ readelf -s crash Symbol table '.symtab' contains 8 entries: Num: Value Size Type Bind Vis Ndx Name ... 6: ffffffffffffffb8 104 FUNC GLOBAL DEFAULT 2 handle_tp Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will point before the actual memory where section 2 is allocated. This is also reported by AddressSanitizer: ================================================================= ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490 READ of size 104 at 0x7c7302fe0000 thread T0 #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76) #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856 #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928 #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930 #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067 #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090 #6 0x000000400c16 in main /poc/poc.c:8 #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4) #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667) #9 0x000000400b34 in _start (/poc/poc+0x400b34) 0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8) allocated by thread T0 here: #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b) #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600) #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018) #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740 The problem here is that currently, libbpf only checks that the program end is within the section bounds. There used to be a check `while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was removed by commit 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions"). Add a check for detecting the overflow of `sec_off + prog_sz` to bpf_object__init_prog to fix this issue. [1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions") Reported-by: lmarch2 <2524158037@qq.com> Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com

Commit 03df156 ("xdp: double protect netdev->xdp_flags with netdev->lock") introduces the netdev lock to xdp_set_features_flag(). The change includes a _locked version of the method, as it is possible for a driver to have already acquired the netdev lock before calling this helper. However, the same applies to xdp_features_(set|clear)_redirect_flags(), which ends up calling the unlocked version of xdp_set_features_flags() leading to deadlocks in GVE, which grabs the netdev lock as part of its suspend, reset, and shutdown processes: [ 833.265543] WARNING: possible recursive locking detected [ 833.270949] 6.15.0-rc1 #6 Tainted: G E [ 833.276271] -------------------------------------------- [ 833.281681] systemd-shutdow/1 is trying to acquire lock: [ 833.287090] ffff949d2b148c68 (&dev->lock){+.+.}-{4:4}, at: xdp_set_features_flag+0x29/0x90 [ 833.295470] [ 833.295470] but task is already holding lock: [ 833.301400] ffff949d2b148c68 (&dev->lock){+.+.}-{4:4}, at: gve_shutdown+0x44/0x90 [gve] [ 833.309508] [ 833.309508] other info that might help us debug this: [ 833.316130] Possible unsafe locking scenario: [ 833.316130] [ 833.322142] CPU0 [ 833.324681] ---- [ 833.327220] lock(&dev->lock); [ 833.330455] lock(&dev->lock); [ 833.333689] [ 833.333689] *** DEADLOCK *** [ 833.333689] [ 833.339701] May be due to missing lock nesting notation [ 833.339701] [ 833.346582] 5 locks held by systemd-shutdow/1: [ 833.351205] #0: ffffffffa9c89130 (system_transition_mutex){+.+.}-{4:4}, at: __se_sys_reboot+0xe6/0x210 [ 833.360695] #1: ffff93b399e5c1b8 (&dev->mutex){....}-{4:4}, at: device_shutdown+0xb4/0x1f0 [ 833.369144] #2: ffff949d19a471b8 (&dev->mutex){....}-{4:4}, at: device_shutdown+0xc2/0x1f0 [ 833.377603] #3: ffffffffa9eca050 (rtnl_mutex){+.+.}-{4:4}, at: gve_shutdown+0x33/0x90 [gve] [ 833.386138] #4: ffff949d2b148c68 (&dev->lock){+.+.}-{4:4}, at: gve_shutdown+0x44/0x90 [gve] Introduce xdp_features_(set|clear)_redirect_target_locked() versions which assume that the netdev lock has already been acquired before setting the XDP feature flag and update GVE to use the locked version. Fixes: 03df156 ("xdp: double protect netdev->xdp_flags with netdev->lock") Tested-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com> Signed-off-by: Joshua Washington <joshwash@google.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20250422011643.3509287-1-joshwash@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

A warning on driver removal started occurring after commit 9dd05df ("net: warn if NAPI instance wasn't shut down"). Disable tx napi before deleting it in mt76_dma_cleanup(). WARNING: CPU: 4 PID: 18828 at net/core/dev.c:7288 __netif_napi_del_locked+0xf0/0x100 CPU: 4 UID: 0 PID: 18828 Comm: modprobe Not tainted 6.15.0-rc4 #4 PREEMPT(lazy) Hardware name: ASUS System Product Name/PRIME X670E-PRO WIFI, BIOS 3035 09/05/2024 RIP: 0010:__netif_napi_del_locked+0xf0/0x100 Call Trace: <TASK> mt76_dma_cleanup+0x54/0x2f0 [mt76] mt7921_pci_remove+0xd5/0x190 [mt7921e] pci_device_remove+0x47/0xc0 device_release_driver_internal+0x19e/0x200 driver_detach+0x48/0x90 bus_remove_driver+0x6d/0xf0 pci_unregister_driver+0x2e/0xb0 __do_sys_delete_module.isra.0+0x197/0x2e0 do_syscall_64+0x7b/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e Tested with mt7921e but the same pattern can be actually applied to other mt76 drivers calling mt76_dma_cleanup() during removal. Tx napi is enabled in their *_dma_init() functions and only toggled off and on again inside their suspend/resume/reset paths. So it should be okay to disable tx napi in such a generic way. Found by Linux Verification Center (linuxtesting.org). Fixes: 2ac515a ("mt76: mt76x02: use napi polling for tx cleanup") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Tested-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com> Link: https://patch.msgid.link/20250506115540.19045-1-pchelkin@ispras.ru Signed-off-by: Felix Fietkau <nbd@nbd.name>

Despite the fact that several lockdep-related checks are skipped when calling trylock* versions of the locking primitives, for example mutex_trylock, each time the mutex is acquired, a held_lock is still placed onto the lockdep stack by __lock_acquire() which is called regardless of whether the trylock* or regular locking API was used. This means that if the caller successfully acquires more than MAX_LOCK_DEPTH locks of the same class, even when using mutex_trylock, lockdep will still complain that the maximum depth of the held lock stack has been reached and disable itself. For example, the following error currently occurs in the ARM version of KVM, once the code tries to lock all vCPUs of a VM configured with more than MAX_LOCK_DEPTH vCPUs, a situation that can easily happen on modern systems, where having more than 48 CPUs is common, and it's also common to run VMs that have vCPU counts approaching that number: [ 328.171264] BUG: MAX_LOCK_DEPTH too low! [ 328.175227] turning off the locking correctness validator. [ 328.180726] Please attach the output of /proc/lock_stat to the bug report [ 328.187531] depth: 48 max: 48! [ 328.190678] 48 locks held by qemu-kvm/11664: [ 328.194957] #0: ffff800086de5ba0 (&kvm->lock){+.+.}-{3:3}, at: kvm_ioctl_create_device+0x174/0x5b0 [ 328.204048] #1: ffff0800e78800b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.212521] #2: ffff07ffeee51e98 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.220991] #3: ffff0800dc7d80b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.229463] #4: ffff07ffe0c980b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.237934] #5: ffff0800a3883c78 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.246405] #6: ffff07fffbe480b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 Luckily, in all instances that require locking all vCPUs, the 'kvm->lock' is taken a priori, and that fact makes it possible to use the little known feature of lockdep, called a 'nest_lock', to avoid this warning and subsequent lockdep self-disablement. The action of 'nested lock' being provided to lockdep's lock_acquire(), causes the lockdep to detect that the top of the held lock stack contains a lock of the same class and then increment its reference counter instead of pushing a new held_lock item onto that stack. See __lock_acquire for more information. Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Message-ID: <20250512180407.659015-2-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_trylock_all_vcpus instead of a custom implementation when locking all vCPUs of a VM, to avoid triggering a lockdep warning, in the case in which the VM is configured to have more than MAX_LOCK_DEPTH vCPUs. This fixes the following false lockdep warning: [ 328.171264] BUG: MAX_LOCK_DEPTH too low! [ 328.175227] turning off the locking correctness validator. [ 328.180726] Please attach the output of /proc/lock_stat to the bug report [ 328.187531] depth: 48 max: 48! [ 328.190678] 48 locks held by qemu-kvm/11664: [ 328.194957] #0: ffff800086de5ba0 (&kvm->lock){+.+.}-{3:3}, at: kvm_ioctl_create_device+0x174/0x5b0 [ 328.204048] #1: ffff0800e78800b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.212521] #2: ffff07ffeee51e98 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.220991] #3: ffff0800dc7d80b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.229463] #4: ffff07ffe0c980b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.237934] #5: ffff0800a3883c78 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 [ 328.246405] #6: ffff07fffbe480b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0 Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Acked-by: Marc Zyngier <maz@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Message-ID: <20250512180407.659015-6-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Running a modified trace-cmd record --nosplice where it does a mmap of the ring buffer when '--nosplice' is set, caused the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc7-test-00002-gfb7d03d8a82f torvalds#551 Not tainted ------------------------------------------------------ trace-cmd/1113 is trying to acquire lock: ffff888100062888 (&buffer->mutex){+.+.}-{4:4}, at: ring_buffer_map+0x11c/0xe70 but task is already holding lock: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&cpu_buffer->mapping_lock){+.+.}-{4:4}: __mutex_lock+0x192/0x18c0 ring_buffer_map+0xcf/0xe70 tracing_buffers_mmap+0x1c4/0x3b0 __mmap_region+0xd8d/0x1f70 do_mmap+0x9d7/0x1010 vm_mmap_pgoff+0x20b/0x390 ksys_mmap_pgoff+0x2e9/0x440 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #4 (&mm->mmap_lock){++++}-{4:4}: __might_fault+0xa5/0x110 _copy_to_user+0x22/0x80 _perf_ioctl+0x61b/0x1b70 perf_ioctl+0x62/0x90 __x64_sys_ioctl+0x134/0x190 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #3 (&cpuctx_mutex){+.+.}-{4:4}: __mutex_lock+0x192/0x18c0 perf_event_init_cpu+0x325/0x7c0 perf_event_init+0x52a/0x5b0 start_kernel+0x263/0x3e0 x86_64_start_reservations+0x24/0x30 x86_64_start_kernel+0x95/0xa0 common_startup_64+0x13e/0x141 -> #2 (pmus_lock){+.+.}-{4:4}: __mutex_lock+0x192/0x18c0 perf_event_init_cpu+0xb7/0x7c0 cpuhp_invoke_callback+0x2c0/0x1030 __cpuhp_invoke_callback_range+0xbf/0x1f0 _cpu_up+0x2e7/0x690 cpu_up+0x117/0x170 cpuhp_bringup_mask+0xd5/0x120 bringup_nonboot_cpus+0x13d/0x170 smp_init+0x2b/0xf0 kernel_init_freeable+0x441/0x6d0 kernel_init+0x1e/0x160 ret_from_fork+0x34/0x70 ret_from_fork_asm+0x1a/0x30 -> #1 (cpu_hotplug_lock){++++}-{0:0}: cpus_read_lock+0x2a/0xd0 ring_buffer_resize+0x610/0x14e0 __tracing_resize_ring_buffer.part.0+0x42/0x120 tracing_set_tracer+0x7bd/0xa80 tracing_set_trace_write+0x132/0x1e0 vfs_write+0x21c/0xe80 ksys_write+0xf9/0x1c0 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&buffer->mutex){+.+.}-{4:4}: __lock_acquire+0x1405/0x2210 lock_acquire+0x174/0x310 __mutex_lock+0x192/0x18c0 ring_buffer_map+0x11c/0xe70 tracing_buffers_mmap+0x1c4/0x3b0 __mmap_region+0xd8d/0x1f70 do_mmap+0x9d7/0x1010 vm_mmap_pgoff+0x20b/0x390 ksys_mmap_pgoff+0x2e9/0x440 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: &buffer->mutex --> &mm->mmap_lock --> &cpu_buffer->mapping_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cpu_buffer->mapping_lock); lock(&mm->mmap_lock); lock(&cpu_buffer->mapping_lock); lock(&buffer->mutex); *** DEADLOCK *** 2 locks held by trace-cmd/1113: #0: ffff888106b847e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x192/0x390 #1: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70 stack backtrace: CPU: 5 UID: 0 PID: 1113 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00002-gfb7d03d8a82f torvalds#551 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6e/0xa0 print_circular_bug.cold+0x178/0x1be check_noncircular+0x146/0x160 __lock_acquire+0x1405/0x2210 lock_acquire+0x174/0x310 ? ring_buffer_map+0x11c/0xe70 ? ring_buffer_map+0x11c/0xe70 ? __mutex_lock+0x169/0x18c0 __mutex_lock+0x192/0x18c0 ? ring_buffer_map+0x11c/0xe70 ? ring_buffer_map+0x11c/0xe70 ? function_trace_call+0x296/0x370 ? __pfx___mutex_lock+0x10/0x10 ? __pfx_function_trace_call+0x10/0x10 ? __pfx___mutex_lock+0x10/0x10 ? _raw_spin_unlock+0x2d/0x50 ? ring_buffer_map+0x11c/0xe70 ? ring_buffer_map+0x11c/0xe70 ? __mutex_lock+0x5/0x18c0 ring_buffer_map+0x11c/0xe70 ? do_raw_spin_lock+0x12d/0x270 ? find_held_lock+0x2b/0x80 ? _raw_spin_unlock+0x2d/0x50 ? rcu_is_watching+0x15/0xb0 ? _raw_spin_unlock+0x2d/0x50 ? trace_preempt_on+0xd0/0x110 tracing_buffers_mmap+0x1c4/0x3b0 __mmap_region+0xd8d/0x1f70 ? ring_buffer_lock_reserve+0x99/0xff0 ? __pfx___mmap_region+0x10/0x10 ? ring_buffer_lock_reserve+0x99/0xff0 ? __pfx_ring_buffer_lock_reserve+0x10/0x10 ? __pfx_ring_buffer_lock_reserve+0x10/0x10 ? bpf_lsm_mmap_addr+0x4/0x10 ? security_mmap_addr+0x46/0xd0 ? lock_is_held_type+0xd9/0x130 do_mmap+0x9d7/0x1010 ? 0xffffffffc0370095 ? __pfx_do_mmap+0x10/0x10 vm_mmap_pgoff+0x20b/0x390 ? __pfx_vm_mmap_pgoff+0x10/0x10 ? 0xffffffffc0370095 ksys_mmap_pgoff+0x2e9/0x440 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fb0963a7de2 Code: 00 00 00 0f 1f 44 00 00 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 3b 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 5b 5d c3 0f 1f 00 48 8b 05 e1 9f 0d 00 64 RSP: 002b:00007ffdcc8fb878 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb0963a7de2 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdcc8fbe68 R14: 00007fb096628000 R15: 00005633e01a5c90 </TASK> The issue is that cpus_read_lock() is taken within buffer->mutex. The memory mapped pages are taken with the mmap_lock held. The buffer->mutex is taken within the cpu_buffer->mapping_lock. There's quite a chain with all these locks, where the deadlock can be fixed by moving the cpus_read_lock() outside the taking of the buffer->mutex. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Link: https://lore.kernel.org/20250527105820.0f45d045@gandalf.local.home Fixes: 117c392 ("ring-buffer: Introducing ring-buffer mapping functions") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

This patch enables support for DYNAMIC_FTRACE_WITH_CALL_OPS on RISC-V. This allows each ftrace callsite to provide an ftrace_ops to the common ftrace trampoline, allowing each callsite to invoke distinct tracer functions without the need to fall back to list processing or to allocate custom trampolines for each callsite. This significantly speeds up cases where multiple distinct trace functions are used and callsites are mostly traced by a single tracer. The idea and most of the implementation is taken from the ARM64's implementation of the same feature. The idea is to place a pointer to the ftrace_ops as a literal at a fixed offset from the function entry point, which can be recovered by the common ftrace trampoline. We use -fpatchable-function-entry to reserve 8 bytes above the function entry by emitting 2 4 byte or 4 2 byte nops depending on the presence of CONFIG_RISCV_ISA_C. These 8 bytes are patched at runtime with a pointer to the associated ftrace_ops for that callsite. Functions are aligned to 8 bytes to make sure that the accesses to this literal are atomic. This approach allows for directly invoking ftrace_ops::func even for ftrace_ops which are dynamically-allocated (or part of a module), without going via ftrace_ops_list_func. We've benchamrked this with the ftrace_ops sample module on Spacemit K1 Jupiter: Without this patch: baseline (Linux rivos 6.14.0-09584-g7d06015d936c #3 SMP Sat Mar 29 +-----------------------+-----------------+----------------------------+ | Number of tracers | Total time (ns) | Per-call average time | |-----------------------+-----------------+----------------------------| | Relevant | Irrelevant | 100000 calls | Total (ns) | Overhead (ns) | |----------+------------+-----------------+------------+---------------| | 0 | 0 | 1357958 | 13 | - | | 0 | 1 | 1302375 | 13 | - | | 0 | 2 | 1302375 | 13 | - | | 0 | 10 | 1379084 | 13 | - | | 0 | 100 | 1302458 | 13 | - | | 0 | 200 | 1302333 | 13 | - | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 13677833 | 136 | 123 | | 1 | 1 | 18500916 | 185 | 172 | | 1 | 2 | 2285645 | 228 | 215 | | 1 | 10 | 58824709 | 588 | 575 | | 1 | 100 | 505141584 | 5051 | 5038 | | 1 | 200 | 1580473126 | 15804 | 15791 | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 13561000 | 135 | 122 | | 2 | 0 | 19707292 | 197 | 184 | | 10 | 0 | 67774750 | 677 | 664 | | 100 | 0 | 714123125 | 7141 | 7128 | | 200 | 0 | 1918065668 | 19180 | 19167 | +----------+------------+-----------------+------------+---------------+ Note: per-call overhead is estimated relative to the baseline case with 0 relevant tracers and 0 irrelevant tracers. With this patch: v4-rc4 (Linux rivos 6.14.0-09598-gd75747611c93 #4 SMP Sat Mar 29 +-----------------------+-----------------+----------------------------+ | Number of tracers | Total time (ns) | Per-call average time | |-----------------------+-----------------+----------------------------| | Relevant | Irrelevant | 100000 calls | Total (ns) | Overhead (ns) | |----------+------------+-----------------+------------+---------------| | 0 | 0 | 1459917 | 14 | - | | 0 | 1 | 1408000 | 14 | - | | 0 | 2 | 1383792 | 13 | - | | 0 | 10 | 1430709 | 14 | - | | 0 | 100 | 1383791 | 13 | - | | 0 | 200 | 1383750 | 13 | - | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 5238041 | 52 | 38 | | 1 | 1 | 5228542 | 52 | 38 | | 1 | 2 | 5325917 | 53 | 40 | | 1 | 10 | 5299667 | 52 | 38 | | 1 | 100 | 5245250 | 52 | 39 | | 1 | 200 | 5238459 | 52 | 39 | |----------+------------+-----------------+------------+---------------| | 1 | 0 | 5239083 | 52 | 38 | | 2 | 0 | 19449417 | 194 | 181 | | 10 | 0 | 67718584 | 677 | 663 | | 100 | 0 | 709840708 | 7098 | 7085 | | 200 | 0 | 2203580626 | 22035 | 22022 | +----------+------------+-----------------+------------+---------------+ Note: per-call overhead is estimated relative to the baseline case with 0 relevant tracers and 0 irrelevant tracers. As can be seen from the above: a) Whenever there is a single relevant tracer function associated with a tracee, the overhead of invoking the tracer is constant, and does not scale with the number of tracers which are *not* associated with that tracee. b) The overhead for a single relevant tracer has dropped to ~1/3 of the overhead prior to this series (from 122ns to 38ns). This is largely due to permitting calls to dynamically-allocated ftrace_ops without going through ftrace_ops_list_func. Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> [update kconfig, asm, refactor] Signed-off-by: Andy Chiu <andybnac@gmail.com> Tested-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20250407180838.42877-10-andybnac@gmail.com Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>

Ido Schimmel says: ==================== seg6: Allow End.X behavior to accept an oif Patches #1-#3 gradually extend the End.X behavior to accept an output interface as an optional argument. This is needed for cases where user space wishes to specify an IPv6 link-local address as the nexthop address. Patch #4 adds test cases to the existing End.X selftest to cover the new functionality. ==================== Link: https://patch.msgid.link/20250612122323.584113-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Subbaraya Sundeep says: ==================== CN20K silicon with mbox support CN20K is the next generation silicon in the Octeon series with various improvements and new features. Along with other changes the mailbox communication mechanism between RVU (Resource virtualization Unit) SRIOV PFs/VFs with Admin function (AF) has also gone through some changes. Some of those changes are - Separate IRQs for mbox request and response/ack. - Configurable mbox size, default being 64KB. - Ability for VFs to communicate with RVU AF instead of going through parent SRIOV PF. Due to more memory requirement due to configurable mbox size, mbox memory will now have to be allocated by - AF (PF0) for communicating with other PFs and all VFs in the system. - PF for communicating with it's child VFs. On previous silicons mbox memory was reserved and configured by firmware. This patch series add basic mbox support for AF (PF0) <=> PFs and PF <=> VFs. AF <=> VFs communication and variable mbox size support will come in later. Patch #1 Supported co-existance of bit encoding PFs and VFs in 16-bit hardware pcifunc format between CN20K silicon and older octeon series. Also exported PF,VF masks and shifts present in mailbox module to all other modules. Patch #2 Added basic mbox operation APIs and structures to support both CN20K and previous version of silicons. Patch #3 This patch adds support for basic mbox infrastructure implementation for CN20K silicon in AF perspective. There are few updates w.r.t MBOX ACK interrupt and offsets in CN20k. Patch #4 Added mbox implementation between NIC PF and AF for CN20K. Patch #5 Added mbox communication support between AF and AF's VFs. Patch #6 This patch adds support for MBOX communication between NIC PF and its VFs. ==================== Link: https://patch.msgid.link/1749639716-13868-1-git-send-email-sbhatta@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Petr Machata says: ==================== ipmr, ip6mr: Allow MC-routing locally-generated MC packets Multicast routing is today handled in the input path. Locally generated MC packets don't hit the IPMR code. Thus if a VXLAN remote address is multicast, the driver needs to set an OIF during route lookup. In practice that means that MC routing configuration needs to be kept in sync with the VXLAN FDB and MDB. Ideally, the VXLAN packets would be routed by the MC routing code instead. To that end, this patchset adds support to route locally generated multicast packets. However, an installation that uses a VXLAN underlay netdevice for which it also has matching MC routes, would get a different routing with this patch. Previously, the MC packets would be delivered directly to the underlay port, whereas now they would be MC-routed. In order to avoid this change in behavior, introduce an IPCB/IP6CB flag. Unless the flag is set, the new MC-routing code is skipped. All this is keyed to a new VXLAN attribute, IFLA_VXLAN_MC_ROUTE. Only when it is set does any of the above engage. In addition to that, and as is the case today with MC forwarding, IPV4_DEVCONF_MC_FORWARDING must be enabled for the netdevice that acts as a source of MC traffic (i.e. the VXLAN PHYS_DEV), so an MC daemon must be attached to the netdevice. When a VXLAN netdevice with a MC remote is brought up, the physical netdevice joins the indicated MC group. This is important for local delivery of MC packets, so it is still necessary to configure a physical netdevice -- the parameter cannot go away. The netdevice would however typically not be a front panel port, but a dummy. An MC daemon would then sit on top of that netdevice as well as any front panel ports that it needs to service, and have routes set up between the two. A way to configure the VXLAN netdevice to take advantage of the new MC routing would be: # ip link add name d up type dummy # ip link add name vx10 up type vxlan id 1000 dstport 4789 \ local 192.0.2.1 group 225.0.0.1 ttl 16 dev d mrcoute # ip link set dev vx10 master br # plus vlans etc. With the following MC routes: (192.0.2.1, 225.0.0.1) iif=d oil=swp1,swp2 # TX route (*, 225.0.0.1) iif=swp1 oil=d,swp2 # RX route (*, 225.0.0.1) iif=swp2 oil=d,swp1 # RX route The RX path has not changed, with the exception of an extra MC hop. Packets are delivered to the front panel port and MC-forwarded to the VXLAN physical port, here "d". Since the port has joined the multicast group, the packets are locally delivered, and end up being processed by the VXLAN netdevice. This patchset is based on earlier patches from Nikolay Aleksandrov and Roopa Prabhu, though it underwent significant changes. Roopa broadly presented the topic on LPC 2019 [0]. Patchset progression: - Patches #1 to #4 add ip_mr_output() - Patches #5 to #10 add ip6_mr_output() - Patch #11 adds the VXLAN bits to enable MR engagement - Patches #12 to #14 prepare selftest libraries - Patch #15 includes a new test suite [0] https://www.youtube.com/watch?v=xlReECfi-uo ==================== Link: https://patch.msgid.link/cover.1750113335.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Before the commit under the Fixes tag below, bnxt_ulp_stop() and bnxt_ulp_start() were always invoked in pairs. After that commit, the new bnxt_ulp_restart() can be invoked after bnxt_ulp_stop() has been called. This may result in the RoCE driver's aux driver .suspend() method being invoked twice. The 2nd bnxt_re_suspend() call will crash when it dereferences a NULL pointer: (NULL ib_device): Handle device suspend call BUG: kernel NULL pointer dereference, address: 0000000000000b78 PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP PTI CPU: 20 UID: 0 PID: 181 Comm: kworker/u96:5 Tainted: G S 6.15.0-rc1 #4 PREEMPT(voluntary) Tainted: [S]=CPU_OUT_OF_SPEC Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017 Workqueue: bnxt_pf_wq bnxt_sp_task [bnxt_en] RIP: 0010:bnxt_re_suspend+0x45/0x1f0 [bnxt_re] Code: 8b 05 a7 3c 5b f5 48 89 44 24 18 31 c0 49 8b 5c 24 08 4d 8b 2c 24 e8 ea 06 0a f4 48 c7 c6 04 60 52 c0 48 89 df e8 1b ce f9 ff <48> 8b 83 78 0b 00 00 48 8b 80 38 03 00 00 a8 40 0f 85 b5 00 00 00 RSP: 0018:ffffa2e84084fd88 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffffb4b6b934 RDI: 00000000ffffffff RBP: ffffa1760954c9c0 R08: 0000000000000000 R09: c0000000ffffdfff R10: 0000000000000001 R11: ffffa2e84084fb50 R12: ffffa176031ef070 R13: ffffa17609775000 R14: ffffa17603adc180 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffffa17daa397000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000b78 CR3: 00000004aaa30003 CR4: 00000000003706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> bnxt_ulp_stop+0x69/0x90 [bnxt_en] bnxt_sp_task+0x678/0x920 [bnxt_en] ? __schedule+0x514/0xf50 process_scheduled_works+0x9d/0x400 worker_thread+0x11c/0x260 ? __pfx_worker_thread+0x10/0x10 kthread+0xfe/0x1e0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2b/0x40 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Check the BNXT_EN_FLAG_ULP_STOPPED flag and do not proceed if the flag is already set. This will preserve the original symmetrical bnxt_ulp_stop() and bnxt_ulp_start(). Also, inside bnxt_ulp_start(), clear the BNXT_EN_FLAG_ULP_STOPPED flag after taking the mutex to avoid any race condition. And for symmetry, only proceed in bnxt_ulp_start() if the BNXT_EN_FLAG_ULP_STOPPED is set. Fixes: 3c163f3 ("bnxt_en: Optimize recovery path ULP locking in the driver") Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com> Co-developed-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250613231841.377988-2-michael.chan@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

says: ==================== net: phy: bcm54811: PHY initialization Proper bcm54811 PHY driver initialization for MII-Lite. The bcm54811 PHY in MLP package must be setup for MII-Lite interface mode by software. Normally, the PHY to MAC interface is selected in hardware by setting the bootstrap pins of the PHY. However, MII and MII-Lite share the same hardware setup and must be distinguished by software, setting appropriate bit in a configuration register. The MII-Lite interface mode is non-standard one, defined by Broadcom for some of their PHYs. The MII-Lite lightness consist in omitting RXER, TXER, CRS and COL signals of the standard MII interface. Absence of COL them makes half-duplex links modes impossible but does not interfere with Broadcom's BroadR-Reach link modes, because they are full-duplex only. To do it in a clean way, MII-Lite must be introduced first, including its limitation to link modes (no half-duplex), because it is a prerequisite for the patch #3 of this series. The patch #4 does not depend on MII-Lite directly but both #3 and #4 are necessary for bcm54811 to work properly without additional configuration steps to be done - for example in the bootloader, before the kernel starts. PATCH 1 - Add MII-Lite PHY interface mode as defined by Broadcom for their two-wire PHYs. It can be used with most Ethernet controllers under certain limitations (no half-duplex link modes etc.). PATCH 2 - Add MII-Lite PHY interface type PATCH 3 - Activation of MII-Lite interface mode on Broadcom bcm5481x PHYs PATCH 4 - Initialize the BCM54811 PHY properly so that it conforms to the datasheet regarding a reserved bit in the LRE Control register, which must be written to zero after every device reset. Ignore the LDS capability bit in LRE Status register on bcm54811. ==================== Link: https://patch.msgid.link/20250708090140.61355-1-kamilh@axis.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

… context The current use of a mutex to protect the notifier hashtable accesses can lead to issues in the atomic context. It results in the below kernel warnings: | BUG: sleeping function called from invalid context at kernel/locking/mutex.c:258 | in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 9, name: kworker/0:0 | preempt_count: 1, expected: 0 | RCU nest depth: 0, expected: 0 | CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted 6.14.0 #4 | Workqueue: ffa_pcpu_irq_notification notif_pcpu_irq_work_fn | Call trace: | show_stack+0x18/0x24 (C) | dump_stack_lvl+0x78/0x90 | dump_stack+0x18/0x24 | __might_resched+0x114/0x170 | __might_sleep+0x48/0x98 | mutex_lock+0x24/0x80 | handle_notif_callbacks+0x54/0xe0 | notif_get_and_handle+0x40/0x88 | generic_exec_single+0x80/0xc0 | smp_call_function_single+0xfc/0x1a0 | notif_pcpu_irq_work_fn+0x2c/0x38 | process_one_work+0x14c/0x2b4 | worker_thread+0x2e4/0x3e0 | kthread+0x13c/0x210 | ret_from_fork+0x10/0x20 To address this, replace the mutex with an rwlock to protect the notifier hashtable accesses. This ensures that read-side locking does not sleep and multiple readers can acquire the lock concurrently, avoiding unnecessary contention and potential deadlocks. Writer access remains exclusive, preserving correctness. This change resolves warnings from lockdep about potential sleep in atomic context. Cc: Jens Wiklander <jens.wiklander@linaro.org> Reported-by: Jérôme Forissier <jerome.forissier@linaro.org> Closes: OP-TEE/optee_os#7394 Fixes: e057344 ("firmware: arm_ffa: Add interfaces to request notification callbacks") Message-Id: <20250528-ffa_notif_fix-v1-3-5ed7bc7f8437@arm.com> Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org> Tested-by: Jens Wiklander <jens.wiklander@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

…ux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.16, take #4 - Gracefully fail initialising pKVM if the interrupt controller isn't GICv3 - Also gracefully fail initialising pKVM if the carveout allocation fails - Fix the computing of the minimum MMIO range required for the host on stage-2 fault - Fix the generation of the GICv3 Maintenance Interrupt in nested mode

pert script tests fails with segmentation fault as below: 92: perf script tests: --- start --- test child forked, pid 103769 DB test [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.012 MB /tmp/perf-test-script.7rbftEpOzX/perf.data (9 samples) ] /usr/libexec/perf-core/tests/shell/script.sh: line 35: 103780 Segmentation fault (core dumped) perf script -i "${perfdatafile}" -s "${db_test}" --- Cleaning up --- ---- end(-1) ---- 92: perf script tests : FAILED! Backtrace pointed to : #0 0x0000000010247dd0 in maps.machine () #1 0x00000000101d178c in db_export.sample () #2 0x00000000103412c8 in python_process_event () #3 0x000000001004eb28 in process_sample_event () #4 0x000000001024fcd0 in machines.deliver_event () #5 0x000000001025005c in perf_session.deliver_event () #6 0x00000000102568b0 in __ordered_events__flush.part.0 () #7 0x0000000010251618 in perf_session.process_events () #8 0x0000000010053620 in cmd_script () #9 0x00000000100b5a28 in run_builtin () #10 0x00000000100b5f94 in handle_internal_command () #11 0x0000000010011114 in main () Further investigation reveals that this occurs in the `perf script tests`, because it uses `db_test.py` script. This script sets `perf_db_export_mode = True`. With `perf_db_export_mode` enabled, if a sample originates from a hypervisor, perf doesn't set maps for "[H]" sample in the code. Consequently, `al->maps` remains NULL when `maps__machine(al->maps)` is called from `db_export__sample`. As al->maps can be NULL in case of Hypervisor samples , use thread->maps because even for Hypervisor sample, machine should exist. If we don't have machine for some reason, return -1 to avoid segmentation fault. Reported-by: Disha Goel <disgoel@linux.ibm.com> Signed-off-by: Aditya Bodkhe <aditya.b1@linux.ibm.com> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Disha Goel <disgoel@linux.ibm.com> Link: https://lore.kernel.org/r/20250429065132.36839-1-adityab1@linux.ibm.com Suggested-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Without the change `perf `hangs up on charaster devices. On my system it's enough to run system-wide sampler for a few seconds to get the hangup: $ perf record -a -g --call-graph=dwarf $ perf report # hung `strace` shows that hangup happens on reading on a character device `/dev/dri/renderD128` $ strace -y -f -p 2780484 strace: Process 2780484 attached pread64(101</dev/dri/renderD128>, strace: Process 2780484 detached It's call trace descends into `elfutils`: $ gdb -p 2780484 (gdb) bt #0 0x00007f5e508f04b7 in __libc_pread64 (fd=101, buf=0x7fff9df7edb0, count=0, offset=0) at ../sysdeps/unix/sysv/linux/pread64.c:25 #1 0x00007f5e52b79515 in read_file () from /<<NIX>>/elfutils-0.192/lib/libelf.so.1 #2 0x00007f5e52b25666 in libdw_open_elf () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #3 0x00007f5e52b25907 in __libdw_open_file () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #4 0x00007f5e52b120a9 in dwfl_report_elf@@ELFUTILS_0.156 () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #5 0x000000000068bf20 in __report_module (al=al@entry=0x7fff9df80010, ip=ip@entry=139803237033216, ui=ui@entry=0x5369b5e0) at util/dso.h:537 #6 0x000000000068c3d1 in report_module (ip=139803237033216, ui=0x5369b5e0) at util/unwind-libdw.c:114 #7 frame_callback (state=0x535aef10, arg=0x5369b5e0) at util/unwind-libdw.c:242 #8 0x00007f5e52b261d3 in dwfl_thread_getframes () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #9 0x00007f5e52b25bdb in get_one_thread_cb () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #10 0x00007f5e52b25faa in dwfl_getthreads () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #11 0x00007f5e52b26514 in dwfl_getthread_frames () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 #12 0x000000000068c6ce in unwind__get_entries (cb=cb@entry=0x5d4620 <unwind_entry>, arg=arg@entry=0x10cd5fa0, thread=thread@entry=0x1076a290, data=data@entry=0x7fff9df80540, max_stack=max_stack@entry=127, best_effort=best_effort@entry=false) at util/thread.h:152 #13 0x00000000005dae95 in thread__resolve_callchain_unwind (evsel=0x106006d0, thread=0x1076a290, cursor=0x10cd5fa0, sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2939 #14 thread__resolve_callchain_unwind (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2920 #15 __thread__resolve_callchain (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, evsel@entry=0x7fff9df80440, sample=0x7fff9df80540, parent=parent@entry=0x7fff9df804a0, root_al=root_al@entry=0x7fff9df80440, max_stack=127, symbols=true) at util/machine.c:2970 #16 0x00000000005d0cb2 in thread__resolve_callchain (thread=<optimized out>, cursor=<optimized out>, evsel=0x7fff9df80440, sample=<optimized out>, parent=0x7fff9df804a0, root_al=0x7fff9df80440, max_stack=127) at util/machine.h:198 #17 sample__resolve_callchain (sample=<optimized out>, cursor=<optimized out>, parent=parent@entry=0x7fff9df804a0, evsel=evsel@entry=0x106006d0, al=al@entry=0x7fff9df80440, max_stack=max_stack@entry=127) at util/callchain.c:1127 #18 0x0000000000617e08 in hist_entry_iter__add (iter=iter@entry=0x7fff9df80480, al=al@entry=0x7fff9df80440, max_stack_depth=127, arg=arg@entry=0x7fff9df81ae0) at util/hist.c:1255 #19 0x000000000045d2d0 in process_sample_event (tool=0x7fff9df81ae0, event=<optimized out>, sample=0x7fff9df80540, evsel=0x106006d0, machine=<optimized out>) at builtin-report.c:334 #20 0x00000000005e3bb1 in perf_session__deliver_event (session=0x105ff2c0, event=0x7f5c7d735ca0, tool=0x7fff9df81ae0, file_offset=2914716832, file_path=0x105ffbf0 "perf.data") at util/session.c:1367 #21 0x00000000005e8d93 in do_flush (oe=0x105ffa50, show_progress=false) at util/ordered-events.c:245 #22 __ordered_events__flush (oe=0x105ffa50, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:324 #23 0x00000000005e1f64 in perf_session__process_user_event (session=0x105ff2c0, event=0x7f5c7d752b18, file_offset=2914835224, file_path=0x105ffbf0 "perf.data") at util/session.c:1419 #24 0x00000000005e47c7 in reader__read_event (rd=rd@entry=0x7fff9df81260, session=session@entry=0x105ff2c0, --Type <RET> for more, q to quit, c to continue without paging-- quit prog=prog@entry=0x7fff9df81220) at util/session.c:2132 #25 0x00000000005e4b37 in reader__process_events (rd=0x7fff9df81260, session=0x105ff2c0, prog=0x7fff9df81220) at util/session.c:2181 #26 __perf_session__process_events (session=0x105ff2c0) at util/session.c:2226 #27 perf_session__process_events (session=session@entry=0x105ff2c0) at util/session.c:2390 #28 0x0000000000460add in __cmd_report (rep=0x7fff9df81ae0) at builtin-report.c:1076 torvalds#29 cmd_report (argc=<optimized out>, argv=<optimized out>) at builtin-report.c:1827 torvalds#30 0x00000000004c5a40 in run_builtin (p=p@entry=0xd8f7f8 <commands+312>, argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:351 torvalds#31 0x00000000004c5d63 in handle_internal_command (argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:404 torvalds#32 0x0000000000442de3 in run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:448 torvalds#33 main (argc=<optimized out>, argv=0x7fff9df844b0) at perf.c:556 The hangup happens because nothing in` perf` or `elfutils` checks if a mapped file is easily readable. The change conservatively skips all non-regular files. Signed-off-by: Sergei Trofimovich <slyich@gmail.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20250505174419.2814857-1-slyich@gmail.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Symbolize stack traces by creating a live machine. Add this functionality to dump_stack and switch dump_stack users to use it. Switch TUI to use it. Add stack traces to the child test function which can be useful to diagnose blocked code. Example output: ``` $ perf test -vv PERF_RECORD_ ... 7: PERF_RECORD_* events & perf_sample fields: 7: PERF_RECORD_* events & perf_sample fields : Running (1 active) ^C Signal (2) while running tests. Terminating tests with the same signal Internal test harness failure. Completing any started tests: : 7: PERF_RECORD_* events & perf_sample fields: ---- unexpected signal (2) ---- #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0 #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 #2 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64 #3 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72 #4 0x7fc12fef1393 in __nanosleep nanosleep.c:26 #5 0x7fc12ff02d68 in __sleep sleep.c:55 #6 0x55788c63196b in test__PERF_RECORD perf-record.c:0 #7 0x55788c620fb0 in run_test_child builtin-test.c:0 #8 0x55788c5bd18d in start_command run-command.c:127 #9 0x55788c621ef3 in __cmd_test builtin-test.c:0 #10 0x55788c6225bf in cmd_test ??:0 #11 0x55788c5afbd0 in run_builtin perf.c:0 #12 0x55788c5afeeb in handle_internal_command perf.c:0 #13 0x55788c52b383 in main ??:0 #14 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74 #15 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 #16 0x55788c52b9d1 in _start ??:0 ---- unexpected signal (2) ---- #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0 #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 #2 0x7fc12fea3a14 in pthread_sigmask@GLIBC_2.2.5 pthread_sigmask.c:45 #3 0x7fc12fe49fd9 in __GI___sigprocmask sigprocmask.c:26 #4 0x7fc12ff2601b in __longjmp_chk longjmp.c:36 #5 0x55788c6210c0 in print_test_result.isra.0 builtin-test.c:0 #6 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 #7 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64 #8 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72 #9 0x7fc12fef1393 in __nanosleep nanosleep.c:26 #10 0x7fc12ff02d68 in __sleep sleep.c:55 #11 0x55788c63196b in test__PERF_RECORD perf-record.c:0 #12 0x55788c620fb0 in run_test_child builtin-test.c:0 #13 0x55788c5bd18d in start_command run-command.c:127 #14 0x55788c621ef3 in __cmd_test builtin-test.c:0 #15 0x55788c6225bf in cmd_test ??:0 #16 0x55788c5afbd0 in run_builtin perf.c:0 #17 0x55788c5afeeb in handle_internal_command perf.c:0 #18 0x55788c52b383 in main ??:0 #19 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74 #20 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 #21 0x55788c52b9d1 in _start ??:0 7: PERF_RECORD_* events & perf_sample fields : Skip (permissions) ``` Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250624210500.2121303-1-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Calling perf top with branch filters enabled on Intel CPU's with branch counters logging (A.K.A LBR event logging [1]) support results in a segfault. $ perf top -e '{cpu_core/cpu-cycles/,cpu_core/event=0xc6,umask=0x3,frontend=0x11,name=frontend_retired_dsb_miss/}' -j any,counter ... Thread 27 "perf" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fffafff76c0 (LWP 949003)] perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653 653 *width = env->cpu_pmu_caps ? env->br_cntr_width : (gdb) bt #0 perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653 #1 0x00000000005b1599 in symbol__account_br_cntr (branch=0x7fffcc3db580, evsel=0xfea2d0, offset=12, br_cntr=8) at util/annotate.c:345 #2 0x00000000005b17fb in symbol__account_cycles (addr=5658172, start=5658160, sym=0x7fffcc0ee420, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:389 #3 0x00000000005b1976 in addr_map_symbol__account_cycles (ams=0x7fffcd7b01d0, start=0x7fffcd7b02b0, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:422 #4 0x000000000068d57f in hist__account_cycles (bs=0x110d288, al=0x7fffafff6540, sample=0x7fffafff6760, nonany_branch_mode=false, total_cycles=0x0, evsel=0xfea2d0) at util/hist.c:2850 #5 0x0000000000446216 in hist_iter__top_callback (iter=0x7fffafff6590, al=0x7fffafff6540, single=true, arg=0x7fffffff9e00) at builtin-top.c:737 #6 0x0000000000689787 in hist_entry_iter__add (iter=0x7fffafff6590, al=0x7fffafff6540, max_stack_depth=127, arg=0x7fffffff9e00) at util/hist.c:1359 #7 0x0000000000446710 in perf_event__process_sample (tool=0x7fffffff9e00, event=0x110d250, evsel=0xfea2d0, sample=0x7fffafff6760, machine=0x108c968) at builtin-top.c:845 #8 0x0000000000447735 in deliver_event (qe=0x7fffffffa120, qevent=0x10fc200) at builtin-top.c:1211 #9 0x000000000064ccae in do_flush (oe=0x7fffffffa120, show_progress=false) at util/ordered-events.c:245 #10 0x000000000064d005 in __ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP, timestamp=0) at util/ordered-events.c:324 #11 0x000000000064d0ef in ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP) at util/ordered-events.c:342 #12 0x00000000004472a9 in process_thread (arg=0x7fffffff9e00) at builtin-top.c:1120 #13 0x00007ffff6e7dba8 in start_thread (arg=<optimized out>) at pthread_create.c:448 #14 0x00007ffff6f01b8c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78 The cause is that perf_env__find_br_cntr_info tries to access a null pointer pmu_caps in the perf_env struct. A similar issue exists for homogeneous core systems which use the cpu_pmu_caps structure. Fix this by populating cpu_pmu_caps and pmu_caps structures with values from sysfs when calling perf top with branch stack sampling enabled. [1], LBR event logging introduced here: https://lore.kernel.org/all/20231025201626.3000228-5-kan.liang@linux.intel.com/ Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Thomas Falcon <thomas.falcon@intel.com> Link: https://lore.kernel.org/r/20250612163659.1357950-2-thomas.falcon@intel.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>

BPF CI testing report a UAF issue: [ 16.446633] BUG: kernel NULL pointer dereference, address: 000000000000003 0 [ 16.447134] #PF: supervisor read access in kernel mod e [ 16.447516] #PF: error_code(0x0000) - not-present pag e [ 16.447878] PGD 0 P4D 0 [ 16.448063] Oops: Oops: 0000 [#1] PREEMPT SMP NOPT I [ 16.448409] CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Tainted: G OE 6.13.0-rc3-g89e8a75fda73-dirty #4 2 [ 16.449124] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODUL E [ 16.449502] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/201 4 [ 16.450201] Workqueue: smc_hs_wq smc_listen_wor k [ 16.450531] RIP: 0010:smc_listen_work+0xc02/0x159 0 [ 16.452158] RSP: 0018:ffffb5ab40053d98 EFLAGS: 0001024 6 [ 16.452526] RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000000000030 0 [ 16.452994] RDX: 0000000000000280 RSI: 00003513840053f0 RDI: 000000000000000 0 [ 16.453492] RBP: ffffa097808e3800 R08: ffffa09782dba1e0 R09: 000000000000000 5 [ 16.453987] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa0978274640 0 [ 16.454497] R13: 0000000000000000 R14: 0000000000000000 R15: ffffa09782d4092 0 [ 16.454996] FS: 0000000000000000(0000) GS:ffffa097bbc00000(0000) knlGS:000000000000000 0 [ 16.455557] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003 3 [ 16.455961] CR2: 0000000000000030 CR3: 0000000102788004 CR4: 0000000000770ef 0 [ 16.456459] PKRU: 5555555 4 [ 16.456654] Call Trace : [ 16.456832] <TASK > [ 16.456989] ? __die+0x23/0x7 0 [ 16.457215] ? page_fault_oops+0x180/0x4c 0 [ 16.457508] ? __lock_acquire+0x3e6/0x249 0 [ 16.457801] ? exc_page_fault+0x68/0x20 0 [ 16.458080] ? asm_exc_page_fault+0x26/0x3 0 [ 16.458389] ? smc_listen_work+0xc02/0x159 0 [ 16.458689] ? smc_listen_work+0xc02/0x159 0 [ 16.458987] ? lock_is_held_type+0x8f/0x10 0 [ 16.459284] process_one_work+0x1ea/0x6d 0 [ 16.459570] worker_thread+0x1c3/0x38 0 [ 16.459839] ? __pfx_worker_thread+0x10/0x1 0 [ 16.460144] kthread+0xe0/0x11 0 [ 16.460372] ? __pfx_kthread+0x10/0x1 0 [ 16.460640] ret_from_fork+0x31/0x5 0 [ 16.460896] ? __pfx_kthread+0x10/0x1 0 [ 16.461166] ret_from_fork_asm+0x1a/0x3 0 [ 16.461453] </TASK > [ 16.461616] Modules linked in: bpf_testmod(OE) [last unloaded: bpf_testmod(OE) ] [ 16.462134] CR2: 000000000000003 0 [ 16.462380] ---[ end trace 0000000000000000 ]--- [ 16.462710] RIP: 0010:smc_listen_work+0xc02/0x1590 The direct cause of this issue is that after smc_listen_out_connected(), newclcsock->sk may be NULL since it will releases the smcsk. Therefore, if the application closes the socket immediately after accept, newclcsock->sk can be NULL. A possible execution order could be as follows: smc_listen_work | userspace ----------------------------------------------------------------- lock_sock(sk) | smc_listen_out_connected() | | \- smc_listen_out | | | \- release_sock | | |- sk->sk_data_ready() | | fd = accept(); | close(fd); | \- socket->sk = NULL; /* newclcsock->sk is NULL now */ SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk)) Since smc_listen_out_connected() will not fail, simply swapping the order of the code can easily fix this issue. Fixes: 3b2dec2 ("net/smc: restructure client and server code in af_smc") Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> Reviewed-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Reviewed-by: Dust Li <dust.li@linux.alibaba.com> Link: https://patch.msgid.link/20250818054618.41615-1-alibuda@linux.alibaba.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

These iterations require the read lock, otherwise RCU lockdep will splat: ============================= WARNING: suspicious RCU usage 6.17.0-rc3-00014-g31419c045d64 #6 Tainted: G O ----------------------------- drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 5 locks held by rtcwake/547: #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98 stack backtrace: CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G O 6.17.0-rc3-00014-g31419c045d64 #6 VOLUNTARY Tainted: [O]=OOT_MODULE Stack: 223721b3a80 6089eac6 00000001 00000001 ffffff00 6089eac6 00000535 6086e528 721b3ac0 6003c294 00000000 60031fc0 Call Trace: [<600407ed>] show_stack+0x10e/0x127 [<6003c294>] dump_stack_lvl+0x77/0xc6 [<6003c2fd>] dump_stack+0x1a/0x20 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e [<603d980f>] device_suspend+0x528/0x541 [<603da24b>] dpm_suspend+0x1a2/0x267 [<603da837>] dpm_suspend_start+0x5d/0x72 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736 [...] Add the fourth argument to the iteration to annotate this and avoid the splat. Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents") Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

mswiatko merged commit 7a1a7af into generic-metadata Aug 9, 2021

mswiatko deleted the generic-metadata-xdp-flags branch August 9, 2021 10:30

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