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@walking-machine walking-machine commented Nov 19, 2021

This PR implements the following:

  1. Get type id from the kernel module side. Getting BTF id is not yet done, but no complex implementation is needed, maybe an export symbol.
  2. Add btf_id field to libbpf btf and fill it in on loading for both module and vmlinux BTF. This required a little bit of refactoring and introduced iterator-style function btf_load_next_with_info(), which is now used for loading both module and vmlinux BTF. This is required for the next step.
  3. Return both type id and BTF id from bpf_core_type_id_kernel(). Earlier only type id was returned despite the fact that llvm enabled the 64 return type for this instruction [1]. This was done as a preparation to the patch [2], which also strongly served as a inspiration for this implementation.
  4. Write an example XDP program that receives the generic metadata from the NIC and compares its type ids acquired from bpf helper and metadata. BTF id is not yet compared, because there is no such field in generic metadata, only BTF id from bpf_core_type_id_kernel() is printed. It can be later verified by running 'bpftool btf list'.

[1] https://reviews.llvm.org/D91489
[2] https://patchwork.kernel.org/project/netdevbpf/patch/20201205025140.443115-1-andrii@kernel.org/

@walking-machine walking-machine changed the title Get vmlinux id without syscall [Draft] Get vmlinux id without syscall Nov 19, 2021
alobakin pushed a commit that referenced this pull request Nov 23, 2021
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>
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Looks like we're (almost) done with the design part!

alobakin pushed a commit that referenced this pull request Nov 30, 2021
…elect()

In resp_mode_select() sanity check the block descriptor len to avoid UAF.

BUG: KASAN: use-after-free in resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509
Read of size 1 at addr ffff888026670f50 by task scsicmd/15032

CPU: 1 PID: 15032 Comm: scsicmd Not tainted 5.15.0-01d0625 #15
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
Call Trace:
 <TASK>
 dump_stack_lvl+0x89/0xb5 lib/dump_stack.c:107
 print_address_description.constprop.9+0x28/0x160 mm/kasan/report.c:257
 kasan_report.cold.14+0x7d/0x117 mm/kasan/report.c:443
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306
 resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509
 schedule_resp+0x4af/0x1a10 drivers/scsi/scsi_debug.c:5483
 scsi_debug_queuecommand+0x8c9/0x1e70 drivers/scsi/scsi_debug.c:7537
 scsi_queue_rq+0x16b4/0x2d10 drivers/scsi/scsi_lib.c:1521
 blk_mq_dispatch_rq_list+0xb9b/0x2700 block/blk-mq.c:1640
 __blk_mq_sched_dispatch_requests+0x28f/0x590 block/blk-mq-sched.c:325
 blk_mq_sched_dispatch_requests+0x105/0x190 block/blk-mq-sched.c:358
 __blk_mq_run_hw_queue+0xe5/0x150 block/blk-mq.c:1762
 __blk_mq_delay_run_hw_queue+0x4f8/0x5c0 block/blk-mq.c:1839
 blk_mq_run_hw_queue+0x18d/0x350 block/blk-mq.c:1891
 blk_mq_sched_insert_request+0x3db/0x4e0 block/blk-mq-sched.c:474
 blk_execute_rq_nowait+0x16b/0x1c0 block/blk-exec.c:63
 sg_common_write.isra.18+0xeb3/0x2000 drivers/scsi/sg.c:837
 sg_new_write.isra.19+0x570/0x8c0 drivers/scsi/sg.c:775
 sg_ioctl_common+0x14d6/0x2710 drivers/scsi/sg.c:941
 sg_ioctl+0xa2/0x180 drivers/scsi/sg.c:1166
 __x64_sys_ioctl+0x19d/0x220 fs/ioctl.c:52
 do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:50
 entry_SYSCALL_64_after_hwframe+0x44/0xae arch/x86/entry/entry_64.S:113

Link: https://lore.kernel.org/r/1637262208-28850-1-git-send-email-george.kennedy@oracle.com
Reported-by: syzkaller <syzkaller@googlegroups.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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Also don't forget to address the old unresolved comments.

alobakin pushed a commit that referenced this pull request Dec 22, 2021
Per HiFive Unmatched schematics, the card detect signal of the
micro SD card is connected to gpio pin #15, which should be
reflected in the DT via the <gpios> property, as described in
Documentation/devicetree/bindings/mmc/mmc-spi-slot.txt.

[1] https://sifive.cdn.prismic.io/sifive/6a06d6c0-6e66-49b5-8e9e-e68ce76f4192_hifive-unmatched-schematics-v3.pdf

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Fixes: d573b55 ("riscv: dts: add initial board data for the SiFive HiFive Unmatched")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
@walking-machine walking-machine force-pushed the generic-metadata-btf-id-from-fd branch 5 times, most recently from b2523c2 to b248f48 Compare February 4, 2022 12:40
@alobakin alobakin changed the base branch from master to bpf-next February 4, 2022 17:13
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The core idea and work with BTF is great, my comments are mostly not closely related to this nitpicks.

@walking-machine walking-machine force-pushed the generic-metadata-btf-id-from-fd branch 2 times, most recently from 0090cf0 to 59e3897 Compare February 10, 2022 14:07
__u32 len = sizeof(*info);
__u64 name = info->name;
__u32 id = start_id;

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I've decided to do it this way in order to separate variables that are constant from start to end of function execution and those that need to be re-assigned every loop

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Also added a hopefully helpful comment on the top

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id and name_len are being passed by a reference in a couple places.
Also, name and name_len seem to be redundant, wouldn't name them critical shortcuts.

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They are not just shortcuts. struct info is memset to zero before getting info from fd

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Right, I thought that we can avoid memsetting it each time, but feels like it's better to leave as it is now.

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TODO : rebase

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I definitely like the direction where this is going to.

@@ -2545,6 +2545,21 @@ static void ice_vsi_assign_bpf_prog(struct ice_vsi *vsi, struct bpf_prog *prog)
WRITE_ONCE(vsi->rx_rings[i]->xdp_prog, vsi->xdp_prog);
}

static void ice_xdp_rings_set_metadata(struct ice_vsi *vsi)
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vsi can be const here BTW, {rx,xdp}_rings are pointers to arrays of pointers, so the VSI structure itself is read-only.

ret = xdp_meta_fill_id_magic(&vsi->xdp_meta_tail, THIS_MODULE,
"xdp_meta_generic");
if (ret)
NL_SET_ERR_MSG_MOD(extack, "Could not fill in xdp meta tail");
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I think we should either stop the operation and return early, or, if you want to still allow use XDP, but without metadata, revert vsi->xdp_metadata_support back to false, so the driver wouldn't even try to build it.

@@ -269,6 +269,7 @@ struct ice_rx_ring {
struct xdp_rxq_info xdp_rxq;
/* CL3 - 3rd cacheline starts here */
u16 q_index; /* Queue number of ring */
u8 xdp_metadata_support:1; /* is xdp metadata supported */
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I'd place it as close as possible to the XDP-related fields to improve cache locality.

@@ -321,6 +324,8 @@ struct ice_tx_ring {
u16 reg_idx; /* HW register index of the ring */
u16 count; /* Number of descriptors */
u16 q_index; /* Queue number of ring */
u8 xdp_metadata_support:1; /* is xdp metadata supported */
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Same here.

@@ -46,6 +46,32 @@ static inline void ice_xdp_ring_update_tail(struct ice_tx_ring *xdp_ring)
writel_relaxed(xdp_ring->next_to_use, xdp_ring->tail);
}

static inline void ice_xdp_set_meta(struct xdp_buff *xdp, union ice_32b_rx_flex_desc *desc,
struct xdp_meta_tail tail)
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desc and tail should be const here.

/*
* Get first BTF with id bigger than the input one.
* Name buffer in the info structure must be initialized by the caller.
*/
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I'd make a kernel-doc from it, you can take e.g. [0] as a reference.

[0] https://elixir.bootlin.com/linux/v5.17-rc3/source/net/core/skbuff.c#L314

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Hm, it won't be consistent with the file

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Aaah, I see. Maybe I'd make a proper kernel-doc here, but then ask upstream folks if we should bother and probably rewrite a doc for the whole libbpf later or just leave those comments as they are.


/* filter BTFs */
if (!info->kernel_btf ||
(!strcmp((char *)name, "vmlinux")) == !load_vmlinux) {
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  1. strncmp().
  2. Cast can be (const char *).
  3. What about an idea of making an opposite to ptr_to_u64() to avoid casting it every time?

err = libbpf_get_error(btf);
if (err) {
pr_warn("failed to load module [%s]'s BTF object #%d: %d\n",
(char *)name, id, err);
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Same here.

{
struct bpf_btf_info info;
struct btf *btf;
char name[64];
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Is this 64 defined somewhere, or just an arbitrary number?

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It's an arbitrary number taken from load_module_btfs()

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Hmm, can we check what are the limits in the kernel functions and/or pahole and create a common definition?

struct module_btf *mod_btf;
struct bpf_btf_info info;
struct btf *btf;
char name[64];
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I see the same info, name + sizeof(name) used nearby both btf_load_next_with_info() invocations, maybe move it there then?

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Well, it was a conscious choice at some point to give the caller the ability to read the info, particularly name, afterwards, but now I see that current consumers do not actually need that. Maybe it was a thing for an older implementation.
Potentially it could be used for some more advanced filtering. Maybe I could leave this function alone, but add a wrapper btf_load_next() that will handle info and name buffers and replace btf_load_next_with_info() -> btf_load_next() in current callers (load_module_btfs() and btf_load_vmlinux_from_kernel()).

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Sound good to me!

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A, ok, after actually doing the changes, I've found a place, where the name buffer is needed. The name needs to be stored stored in struct module_btf, so I guess I won't do a wrapper, because in such case it'll only be useful for vmlinux loading


ret = 1;
prog_fd = bpf_program__fd(skel->progs.xdp_meta_prog);
if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
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Hmm, since this Aug-Sep we now have xdp_sample_user infra (e.g. [0]), would you mind trying to use it in this sample?

[0] e531a22

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Well, looks a little bit like an overkill for this sample, but I guess it could reduce the code size a little bit and unify the error output with other samples.


hash = BPF_CORE_READ(data_meta, rx_hash);
rxcvid = BPF_CORE_READ(data_meta, rx_vid);
bpf_printk("Metadata. Hash: 0x%x, VID: %d\n", hash, rxcvid);
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Could you please read some bitfields from xdp_meta_generic::rx_flags here? That would show how to work with them.
XDP_META_* definitions should be also converted to enum (you can place them all in one enum, together with XDP_META_ALIGN) in order to be able to use them from BPF progs.

@walking-machine walking-machine force-pushed the generic-metadata-btf-id-from-fd branch 2 times, most recently from 2a84b87 to 46c2247 Compare March 10, 2022 16:35
alobakin and others added 7 commits March 25, 2022 10:27
In order to be able to pass more flags and/or other options to
sample_install_xdp() from userland programs built ontop of this
framework, make it consume a const pointer to a structure with
all the parameters needed to initialize the sample instead of a
set of parameters which doesn't scale.
Adjust all the samples accordingly.

Signed-off-by: Alexander Lobakin <alexandr.lobakin@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>
TODO

Signed-off-by: Michal Swiatkowski <michal.swiatkowski@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Helper fills in 3 last fields of generic xdp meta
based on requesting module and type name.

Module can be NULL, in this case we fall back on vmlinux BTF.
If module is not NULL, function is still capable of detecting
and handling vmlinux types.

Signed-off-by: Ederson de Souza <ederson.desouza@intel.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
As starting point add vlan id and rss hash if xdp metadata is supported.

Add xd_metadata_support field in VSI to allow easy passing this value to
ring configuration.

Signed-off-by: Michal Swiatkowski <michal.swiatkowski@intel.com>
Fill in remaining hints fields, most importantly
BTF id, type id and magic, which later allows hints
consumers to clearly identify the type.

Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Introduce id field to the userspace btf struct,
it allows to clearly identify btf's in-kernel counterpart.

Unify the way vmlinux and module BTFs are loaded
by encapsulating part of module BTF loading code
in a function that picks the first BTF after an id,
which complies with criteria.

For vmlinux, try to acquire it in the new way,
resort to old fs way, if not successful.

Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
alobakin pushed a commit that referenced this pull request Oct 4, 2023
The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
alobakin pushed a commit that referenced this pull request Oct 4, 2023
…roy()

After the commit in Fixes:, if a module that created a slab cache does not
release all of its allocated objects before destroying the cache (at rmmod
time), we might end up releasing the kmem_cache object without removing it
from the slab_caches list thus corrupting the list as kmem_cache_destroy()
ignores the return value from shutdown_cache(), which in turn never removes
the kmem_cache object from slabs_list in case __kmem_cache_shutdown() fails
to release all of the cache's slabs.

This is easily observable on a kernel built with CONFIG_DEBUG_LIST=y
as after that ill release the system will immediately trip on list_add,
or list_del, assertions similar to the one shown below as soon as another
kmem_cache gets created, or destroyed:

  [ 1041.213632] list_del corruption. next->prev should be ffff89f596fb5768, but was 52f1e5016aeee75d. (next=ffff89f595a1b268)
  [ 1041.219165] ------------[ cut here ]------------
  [ 1041.221517] kernel BUG at lib/list_debug.c:62!
  [ 1041.223452] invalid opcode: 0000 [#1] PREEMPT SMP PTI
  [ 1041.225408] CPU: 2 PID: 1852 Comm: rmmod Kdump: loaded Tainted: G    B   W  OE      6.5.0 #15
  [ 1041.228244] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20230524-3.fc37 05/24/2023
  [ 1041.231212] RIP: 0010:__list_del_entry_valid+0xae/0xb0

Another quick way to trigger this issue, in a kernel with CONFIG_SLUB=y,
is to set slub_debug to poison the released objects and then just run
cat /proc/slabinfo after removing the module that leaks slab objects,
in which case the kernel will panic:

  [   50.954843] general protection fault, probably for non-canonical address 0xa56b6b6b6b6b6b8b: 0000 [#1] PREEMPT SMP PTI
  [   50.961545] CPU: 2 PID: 1495 Comm: cat Kdump: loaded Tainted: G    B   W  OE      6.5.0 #15
  [   50.966808] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20230524-3.fc37 05/24/2023
  [   50.972663] RIP: 0010:get_slabinfo+0x42/0xf0

This patch fixes this issue by properly checking shutdown_cache()'s
return value before taking the kmem_cache_release() branch.

Fixes: 0495e33 ("mm/slab_common: Deleting kobject in kmem_cache_destroy() without holding slab_mutex/cpu_hotplug_lock")
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
alobakin pushed a commit that referenced this pull request Oct 4, 2023
Fix an error detected by memory sanitizer:
```
==4033==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x55fb0fbedfc7 in read_alias_info tools/perf/util/pmu.c:457:6
    #1 0x55fb0fbea339 in check_info_data tools/perf/util/pmu.c:1434:2
    #2 0x55fb0fbea339 in perf_pmu__check_alias tools/perf/util/pmu.c:1504:9
    #3 0x55fb0fbdca85 in parse_events_add_pmu tools/perf/util/parse-events.c:1429:32
    #4 0x55fb0f965230 in parse_events_parse tools/perf/util/parse-events.y:299:6
    #5 0x55fb0fbdf6b2 in parse_events__scanner tools/perf/util/parse-events.c:1822:8
    #6 0x55fb0fbdf8c1 in __parse_events tools/perf/util/parse-events.c:2094:8
    #7 0x55fb0fa8ffa9 in parse_events tools/perf/util/parse-events.h:41:9
    #8 0x55fb0fa8ffa9 in test_event tools/perf/tests/parse-events.c:2393:8
    #9 0x55fb0fa8f458 in test__pmu_events tools/perf/tests/parse-events.c:2551:15
    #10 0x55fb0fa6d93f in run_test tools/perf/tests/builtin-test.c:242:9
    #11 0x55fb0fa6d93f in test_and_print tools/perf/tests/builtin-test.c:271:8
    #12 0x55fb0fa6d082 in __cmd_test tools/perf/tests/builtin-test.c:442:5
    #13 0x55fb0fa6d082 in cmd_test tools/perf/tests/builtin-test.c:564:9
    #14 0x55fb0f942720 in run_builtin tools/perf/perf.c:322:11
    #15 0x55fb0f942486 in handle_internal_command tools/perf/perf.c:375:8
    #16 0x55fb0f941dab in run_argv tools/perf/perf.c:419:2
    #17 0x55fb0f941dab in main tools/perf/perf.c:535:3
```

Fixes: 7b723db ("perf pmu: Be lazy about loading event info files from sysfs")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20230914022425.1489035-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
alobakin pushed a commit that referenced this pull request Oct 4, 2023
The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
alobakin pushed a commit that referenced this pull request Nov 30, 2023
Petr Machata says:

====================
mlxsw: Support CFF flood mode

The registers to configure to initialize a flood table differ between the
controlled and CFF flood modes. In therefore needs to be an op. Add it,
hook up the current init to the existing families, and invoke the op.

PGT is an in-HW table that maps addresses to sets of ports. Then when some
HW process needs a set of ports as an argument, instead of embedding the
actual set in the dynamic configuration, what gets configured is the
address referencing the set. The HW then works with the appropriate PGT
entry.

Among other allocations, the PGT currently contains two large blocks for
bridge flooding: one for 802.1q and one for 802.1d. Within each of these
blocks are three tables, for unknown-unicast, multicast and broadcast
flooding:

      . . . |    802.1q    |    802.1d    | . . .
            | UC | MC | BC | UC | MC | BC |
             \______ _____/ \_____ ______/
                    v             v
                   FID flood vectors

Thus each FID (which corresponds to an 802.1d bridge or one VLAN in an
802.1q bridge) uses three flood vectors spread across a fairly large region
of PGT.

This way of organizing the flood table (called "controlled") is not very
flexible. E.g. to decrease a bridge scale and store more IP MC vectors, one
would need to completely rewrite the bridge PGT blocks, or resort to hacks
such as storing individual MC flood vectors into unused part of the bridge
table.

In order to address these shortcomings, Spectrum-2 and above support what
is called CFF flood mode, for Compressed FID Flooding. In CFF flood mode,
each FID has a little table of its own, with three entries adjacent to each
other, one for unknown-UC, one for MC, one for BC. This allows for a much
more fine-grained approach to PGT management, where bits of it are
allocated on demand.

      . . . | FID | FID | FID | FID | FID | . . .
            |U|M|B|U|M|B|U|M|B|U|M|B|U|M|B|
             \_____________ _____________/
                           v
                   FID flood vectors

Besides the FID table organization, the CFF flood mode also impacts Router
Subport (RSP) table. This table contains flood vectors for rFIDs, which are
FIDs that reference front panel ports or LAGs. The RSP table contains two
entries per front panel port and LAG, one for unknown-UC traffic, and one
for everything else. Currently, the FW allocates and manages the table in
its own part of PGT. rFIDs are marked with flood_rsp bit and managed
specially. In CFF mode, rFIDs are managed as all other FIDs. The driver
therefore has to allocate and maintain the flood vectors. Like with bridge
FIDs, this is more work, but increases flexibility of the system.

The FW currently supports both the controlled and CFF flood modes. To shed
complexity, in the future it should only support CFF flood mode. Hence this
patchset, which adds CFF flood mode support to mlxsw.

Since mlxsw needs to maintain both the controlled mode as well as CFF mode
support, we will keep the layout as compatible as possible. The bridge
tables will stay in the same overall shape, just their inner organization
will change from flood mode -> FID to FID -> flood mode. Likewise will RSP
be kept as a contiguous block of PGT memory, as was the case when the FW
maintained it.

- The way FIDs get configured under the CFF flood mode differs from the
  currently used controlled mode. The simple approach of having several
  globally visible arrays for spectrum.c to statically choose from no
  longer works.

  Patch #1 thus privatizes all FID initialization and finalization logic,
  and exposes it as ops instead.

- Patch #2 renames the ops that are specific to the controlled mode, to
  make room in the namespace for the CFF variants.

  Patch #3 extracts a helper to compute flood table base out of
  mlxsw_sp_fid_flood_table_mid().

- The op fid_setup configured fid_offset, i.e. the number of this FID
  within its family. For rFIDs in CFF mode, to determine this number, the
  driver will need to do fallible queries.

  Thus in patch #4, make the FID setup operation fallible as well.

- Flood mode initialization routine differs between the controlled and CFF
  flood modes. The controlled mode needs to configure flood table layout,
  which the CFF mode does not need to do.

  In patch #5, move mlxsw_sp_fid_flood_table_init() up so that the
  following patch can make use of it.

  In patch #6, add an op to be invoked per table (if defined).

- The current way of determining PGT allocation size depends on the number
  of FIDs and number of flood tables. RFIDs however have PGT footprint
  depending not on number of FIDs, but on number of ports and LAGs, because
  which ports an rFID should flood to does not depend on the FID itself,
  but on the port or LAG that it references.

  Therefore in patch #7, add FID family ops for determining PGT allocation
  size.

- As elaborated above, layout of PGT will differ between controlled and CFF
  flood modes. In CFF mode, it will further differ between rFIDs and other
  FIDs (as described at previous patch). The way to pack the SFMR register
  to configure a FID will likewise differ from controlled to CFF.

  Thus in patches #8 and #9 add FID family ops to determine PGT base
  address for a FID and to pack SFMR.

- Patches #10 and #11 add more bits for RSP support. In patch #10, add a
  new traffic type enumerator, for non-UC traffic. This is a combination of
  BC and MC traffic, but the way that mlxsw maps these mnemonic names to
  actual traffic type configurations requires that we have a new name to
  describe this class of traffic.

  Patch #11 then adds hooks necessary for RSP table maintenance. As ports
  come and go, and join and leave LAGs, it is necessary to update flood
  vectors that the rFIDs use. These new hooks will make that possible.

- Patches #12, #13 and #14 introduce flood profiles. These have been
  implicit so far, but the way that CFF flood mode works with profile IDs
  requires that we make them explicit.

  Thus in patch #12, introduce flood profile objects as a set of flood
  tables that FID families then refer to. The FID code currently only
  uses a single flood profile.

  In patch #13, add a flood profile ID to flood profile objects.

  In patch #14, when in CFF mode, configure SFFP according to the existing
  flood profiles (or the one that exists as of that point).

- Patches #15 and #16 add code to implement, respectively, bridge FIDs and
  RSP FIDs in CFF mode.

- In patch #17, toggle flood_mode_prefer_cff on Spectrum-2 and above, which
  makes the newly-added code live.
====================

Link: https://lore.kernel.org/r/cover.1701183891.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
alobakin pushed a commit that referenced this pull request Dec 18, 2023
When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   #15 [ffff88aa841efb88] device_del at ffffffff82179d23
   #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn
Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com>
Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn>
Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
alobakin pushed a commit that referenced this pull request Dec 22, 2023
…s_del_by_dev()

I got the below warning trace:

WARNING: CPU: 4 PID: 4056 at net/core/dev.c:11066 unregister_netdevice_many_notify
CPU: 4 PID: 4056 Comm: ip Not tainted 6.7.0-rc4+ #15
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:unregister_netdevice_many_notify+0x9a4/0x9b0
Call Trace:
 rtnl_dellink
 rtnetlink_rcv_msg
 netlink_rcv_skb
 netlink_unicast
 netlink_sendmsg
 __sock_sendmsg
 ____sys_sendmsg
 ___sys_sendmsg
 __sys_sendmsg
 do_syscall_64
 entry_SYSCALL_64_after_hwframe

It can be repoduced via:

    ip netns add ns1
    ip netns exec ns1 ip link add bond0 type bond mode 0
    ip netns exec ns1 ip link add bond_slave_1 type veth peer veth2
    ip netns exec ns1 ip link set bond_slave_1 master bond0
[1] ip netns exec ns1 ethtool -K bond0 rx-vlan-filter off
[2] ip netns exec ns1 ip link add link bond_slave_1 name bond_slave_1.0 type vlan id 0
[3] ip netns exec ns1 ip link add link bond0 name bond0.0 type vlan id 0
[4] ip netns exec ns1 ip link set bond_slave_1 nomaster
[5] ip netns exec ns1 ip link del veth2
    ip netns del ns1

This is all caused by command [1] turning off the rx-vlan-filter function
of bond0. The reason is the same as commit 01f4fd2 ("bonding: Fix
incorrect deletion of ETH_P_8021AD protocol vid from slaves"). Commands
[2] [3] add the same vid to slave and master respectively, causing
command [4] to empty slave->vlan_info. The following command [5] triggers
this problem.

To fix this problem, we should add VLAN_FILTER feature checks in
vlan_vids_add_by_dev() and vlan_vids_del_by_dev() to prevent incorrect
addition or deletion of vlan_vid information.

Fixes: 348a144 ("vlan: introduce functions to do mass addition/deletion of vids by another device")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
alobakin pushed a commit that referenced this pull request Apr 4, 2024
Petr Machata says:

====================
mlxsw: Preparations for improving performance

Amit Cohen writes:

mlxsw driver will use NAPI for event processing in a next patch set.
Some additional improvements will be added later. This patch set
prepares the code for NAPI usage and refactor some relevant areas. See
more details in commit messages.

Patch Set overview:
Patches #1-#2 are preparations for patch #3
Patch #3 setups tasklets as part of queue initializtion
Patch #4 removes handling of unlikely scenario
Patch #5 removes unused counters
Patch #6 makes style change in mlxsw_pci_eq_tasklet()
Patch #7-#10 poll command interface instead of EQ0 usage
Patches #11-#12 make style change and break the function
mlxsw_pci_cq_tasklet()
Patches #13-#14 remove functions which can be replaced by a stored value
Patch #15 improves accessing to descriptor queue instance
====================

Link: https://lore.kernel.org/r/cover.1712062203.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
alobakin pushed a commit that referenced this pull request Apr 19, 2024
vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
alobakin pushed a commit that referenced this pull request May 22, 2024
ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Li Dong <lidong@vivo.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Paran Lee <p4ranlee@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240507183545.1236093-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
alobakin pushed a commit that referenced this pull request Jun 14, 2024
We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
alobakin pushed a commit that referenced this pull request Jun 25, 2024
Make the short function kvaser_pciefd_set_tx_irq inline. This function
is effectively three lines long and therefore inlining it should be
OK according to rule #15 of the Linux kernel coding style.

Signed-off-by: Martin Jocic <martin.jocic@kvaser.com>
Link: https://lore.kernel.org/all/20240614151524.2718287-5-martin.jocic@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
alobakin pushed a commit that referenced this pull request Jun 28, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
alobakin pushed a commit that referenced this pull request Jul 1, 2024
…rnel/git/netfilter/nf-next into main

Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for net-next:

Patch #1 to #11 to shrink memory consumption for transaction objects:

  struct nft_trans_chain { /* size: 120 (-32), cachelines: 2, members: 10 */
  struct nft_trans_elem { /* size: 72 (-40), cachelines: 2, members: 4 */
  struct nft_trans_flowtable { /* size: 80 (-48), cachelines: 2, members: 5 */
  struct nft_trans_obj { /* size: 72 (-40), cachelines: 2, members: 4 */
  struct nft_trans_rule { /* size: 80 (-32), cachelines: 2, members: 6 */
  struct nft_trans_set { /* size: 96 (-24), cachelines: 2, members: 8 */
  struct nft_trans_table { /* size: 56 (-40), cachelines: 1, members: 2 */

  struct nft_trans_elem can now be allocated from kmalloc-96 instead of
  kmalloc-128 slab.

  Series from Florian Westphal. For the record, I have mangled patch #1
  to add nft_trans_container_*() and use if for every transaction object.
   I have also added BUILD_BUG_ON to ensure struct nft_trans always comes
  at the beginning of the container transaction object. And few minor
  cleanups, any new bugs are of my own.

Patch #12 simplify check for SCTP GSO in IPVS, from Ismael Luceno.

Patch #13 nf_conncount key length remains in the u32 bound, from Yunjian Wang.

Patch #14 removes unnecessary check for CTA_TIMEOUT_L3PROTO when setting
          default conntrack timeouts via nfnetlink_cttimeout API, from
          Lin Ma.

Patch #15 updates NFT_SECMARK_CTX_MAXLEN to 4096, SELinux could use
          larger secctx names than the existing 256 bytes length.

Patch #16 adds a selftest to exercise nfnetlink_queue listeners leaving
          nfnetlink_queue, from Florian Westphal.

Patch #17 increases hitcount from 255 to 65535 in xt_recent, from Phil Sutter.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
alobakin pushed a commit that referenced this pull request Jul 24, 2024
With latest llvm19, the selftest iters/iter_arr_with_actual_elem_count
failed with -mcpu=v4.

The following are the details:
  0: R1=ctx() R10=fp0
  ; int iter_arr_with_actual_elem_count(const void *ctx) @ iters.c:1420
  0: (b4) w7 = 0                        ; R7_w=0
  ; int i, n = loop_data.n, sum = 0; @ iters.c:1422
  1: (18) r1 = 0xffffc90000191478       ; R1_w=map_value(map=iters.bss,ks=4,vs=1280,off=1144)
  3: (61) r6 = *(u32 *)(r1 +128)        ; R1_w=map_value(map=iters.bss,ks=4,vs=1280,off=1144) R6_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff))
  ; if (n > ARRAY_SIZE(loop_data.data)) @ iters.c:1424
  4: (26) if w6 > 0x20 goto pc+27       ; R6_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f))
  5: (bf) r8 = r10                      ; R8_w=fp0 R10=fp0
  6: (07) r8 += -8                      ; R8_w=fp-8
  ; bpf_for(i, 0, n) { @ iters.c:1427
  7: (bf) r1 = r8                       ; R1_w=fp-8 R8_w=fp-8
  8: (b4) w2 = 0                        ; R2_w=0
  9: (bc) w3 = w6                       ; R3_w=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R6_w=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f))
  10: (85) call bpf_iter_num_new#45179          ; R0=scalar() fp-8=iter_num(ref_id=2,state=active,depth=0) refs=2
  11: (bf) r1 = r8                      ; R1=fp-8 R8=fp-8 refs=2
  12: (85) call bpf_iter_num_next#45181 13: R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) R6=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R7=0 R8=fp-8 R10=fp0 fp-8=iter_num(ref_id=2,state=active,depth=1) refs=2
  ; bpf_for(i, 0, n) { @ iters.c:1427
  13: (15) if r0 == 0x0 goto pc+2       ; R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) refs=2
  14: (81) r1 = *(s32 *)(r0 +0)         ; R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) R1_w=scalar(smin=0xffffffff80000000,smax=0x7fffffff) refs=2
  15: (ae) if w1 < w6 goto pc+4 20: R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) R1=scalar(smin=0xffffffff80000000,smax=smax32=umax32=31,umax=0xffffffff0000001f,smin32=0,var_off=(0x0; 0xffffffff0000001f)) R6=scalar(id=1,smin=umin=smin32=umin32=1,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R7=0 R8=fp-8 R10=fp0 fp-8=iter_num(ref_id=2,state=active,depth=1) refs=2
  ; sum += loop_data.data[i]; @ iters.c:1429
  20: (67) r1 <<= 2                     ; R1_w=scalar(smax=0x7ffffffc0000007c,umax=0xfffffffc0000007c,smin32=0,smax32=umax32=124,var_off=(0x0; 0xfffffffc0000007c)) refs=2
  21: (18) r2 = 0xffffc90000191478      ; R2_w=map_value(map=iters.bss,ks=4,vs=1280,off=1144) refs=2
  23: (0f) r2 += r1
  math between map_value pointer and register with unbounded min value is not allowed

The source code:
  int iter_arr_with_actual_elem_count(const void *ctx)
  {
        int i, n = loop_data.n, sum = 0;

        if (n > ARRAY_SIZE(loop_data.data))
                return 0;

        bpf_for(i, 0, n) {
                /* no rechecking of i against ARRAY_SIZE(loop_data.n) */
                sum += loop_data.data[i];
        }

        return sum;
  }

The insn #14 is a sign-extenstion load which is related to 'int i'.
The insn #15 did a subreg comparision. Note that smin=0xffffffff80000000 and this caused later
insn #23 failed verification due to unbounded min value.

Actually insn #15 R1 smin range can be better. Before insn #15, we have
  R1_w=scalar(smin=0xffffffff80000000,smax=0x7fffffff)
With the above range, we know for R1, upper 32bit can only be 0xffffffff or 0.
Otherwise, the value range for R1 could be beyond [smin=0xffffffff80000000,smax=0x7fffffff].

After insn #15, for the true patch, we know smin32=0 and smax32=32. With the upper 32bit 0xffffffff,
then the corresponding value is [0xffffffff00000000, 0xffffffff00000020]. The range is
obviously beyond the original range [smin=0xffffffff80000000,smax=0x7fffffff] and the
range is not possible. So the upper 32bit must be 0, which implies smin = smin32 and
smax = smax32.

This patch fixed the issue by adding additional register deduction after 32-bit compare
insn. If the signed 32-bit register range is non-negative then 64-bit smin is
in range of [S32_MIN, S32_MAX], then the actual 64-bit smin/smax should be the same
as 32-bit smin32/smax32.

With this patch, iters/iter_arr_with_actual_elem_count succeeded with better register range:

from 15 to 20: R0=rdonly_mem(id=7,ref_obj_id=2,sz=4) R1_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=31,var_off=(0x0; 0x1f)) R6=scalar(id=1,smin=umin=smin32=umin32=1,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R7=scalar(id=9,smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R8=scalar(id=9,smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R10=fp0 fp-8=iter_num(ref_id=2,state=active,depth=3) refs=2

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240723162933.2731620-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
alobakin pushed a commit that referenced this pull request Aug 30, 2024
A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <jamie.bainbridge@gmail.com>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
alobakin pushed a commit that referenced this pull request Oct 9, 2024
Daniel Machon says:

====================
net: sparx5: prepare for lan969x switch driver

== Description:

This series is the first of a multi-part series, that prepares and adds
support for the new lan969x switch driver.

The upstreaming efforts is split into multiple series (might change a
bit as we go along):

    1) Prepare the Sparx5 driver for lan969x (this series)
    2) Add support lan969x (same basic features as Sparx5 provides +
       RGMII, excl.  FDMA and VCAP)
    3) Add support for lan969x FDMA
    4) Add support for lan969x VCAP

== Lan969x in short:

The lan969x Ethernet switch family [1] provides a rich set of
switching features and port configurations (up to 30 ports) from 10Mbps
to 10Gbps, with support for RGMII, SGMII, QSGMII, USGMII, and USXGMII,
ideal for industrial & process automation infrastructure applications,
transport, grid automation, power substation automation, and ring &
intra-ring topologies. The LAN969x family is hardware and software
compatible and scalable supporting 46Gbps to 102Gbps switch bandwidths.

== Preparing Sparx5 for lan969x:

The lan969x switch chip reuses many of the IP's of the Sparx5 switch
chip, therefore it has been decided to add support through the existing
Sparx5 driver, in order to avoid a bunch of duplicate code. However, in
order to reuse the Sparx5 switch driver, we have to introduce some
mechanisms to handle the chip differences that are there.  These
mechanisms are:

    - Platform match data to contain all the differences that needs to
      be handled (constants, ops etc.)

    - Register macro indirection layer so that we can reuse the existing
      register macros.

    - Function for branching out on platform type where required.

In some places we ops out functions and in other places we branch on the
chip type. Exactly when we choose one over the other, is an estimate in
each case.

After this series is applied, the Sparx5 driver will be prepared for
lan969x and still function exactly as before.

== Patch breakdown:

Patch #1        adds private match data

Patch #2        adds register macro indirection layer

Patch #3-#4     does some preparation work

Patch #5-#7     adds chip constants and updates the code to use them

Patch #8-#13    adds and uses ops for handling functions differently on the
                two platforms.

Patch #14       adds and uses a macro for branching out on the chip type.

Patch #15 (NEW) redefines macros for internal ports and PGID's.

[1] https://www.microchip.com/en-us/product/lan9698

To: David S. Miller <davem@davemloft.net>
To: Eric Dumazet <edumazet@google.com>
To: Jakub Kicinski <kuba@kernel.org>
To: Paolo Abeni <pabeni@redhat.com>
To: Lars Povlsen <lars.povlsen@microchip.com>
To: Steen Hegelund <Steen.Hegelund@microchip.com>
To: horatiu.vultur@microchip.com
To: jensemil.schulzostergaard@microchip.com
To: UNGLinuxDriver@microchip.com
To: Richard Cochran <richardcochran@gmail.com>
To: horms@kernel.org
To: justinstitt@google.com
To: gal@nvidia.com
To: aakash.r.menon@gmail.com
To: jacob.e.keller@intel.com
To: ast@fiberby.net
Cc: netdev@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
====================

Link: https://patch.msgid.link/20241004-b4-sparx5-lan969x-switch-driver-v2-0-d3290f581663@microchip.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
alobakin pushed a commit that referenced this pull request Nov 4, 2024
Daniel Machon says:

====================
net: sparx5: add support for lan969x switch device

== Description:

This series is the second of a multi-part series, that prepares and adds
support for the new lan969x switch driver.

The upstreaming efforts is split into multiple series (might change a
bit as we go along):

        1) Prepare the Sparx5 driver for lan969x (merged)

    --> 2) add support lan969x (same basic features as Sparx5
           provides excl. FDMA and VCAP).

        3) Add support for lan969x VCAP, FDMA and RGMII

== Lan969x in short:

The lan969x Ethernet switch family [1] provides a rich set of
switching features and port configurations (up to 30 ports) from 10Mbps
to 10Gbps, with support for RGMII, SGMII, QSGMII, USGMII, and USXGMII,
ideal for industrial & process automation infrastructure applications,
transport, grid automation, power substation automation, and ring &
intra-ring topologies. The LAN969x family is hardware and software
compatible and scalable supporting 46Gbps to 102Gbps switch bandwidths.

== Preparing Sparx5 for lan969x:

The main preparation work for lan969x has already been merged [1].

After this series is applied, lan969x will have the same functionality
as Sparx5, except for VCAP and FDMA support. QoS features that requires
the VCAP (e.g. PSFP, port mirroring) will obviously not work until VCAP
support is added later.

== Patch breakdown:

Patch #1-#4  do some preparation work for lan969x

Patch #5     adds new registers required by lan969x

Patch #6     adds initial match data for all lan969x targets

Patch #7     defines the lan969x register differences

Patch #8     adds lan969x constants to match data

Patch #9     adds some lan969x ops in bulk

Patch #10    adds PTP function to ops

Patch #11    adds lan969x_calendar.c for calculating the calendar

Patch #12    makes additional use of the is_sparx5() macro to branch out
             in certain places.

Patch #13    documents lan969x in the dt-bindings

Patch #14    adds lan969x compatible string to sparx5 driver

Patch #15    introduces new concept of per-target features

[1] https://lore.kernel.org/netdev/20241004-b4-sparx5-lan969x-switch-driver-v2-0-d3290f581663@microchip.com/

v1: https://lore.kernel.org/20241021-sparx5-lan969x-switch-driver-2-v1-0-c8c49ef21e0f@microchip.com
====================

Link: https://patch.msgid.link/20241024-sparx5-lan969x-switch-driver-2-v2-0-a0b5fae88a0f@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
alobakin pushed a commit that referenced this pull request Nov 12, 2024
KASAN reports an out of bounds read:
BUG: KASAN: slab-out-of-bounds in __kuid_val include/linux/uidgid.h:36
BUG: KASAN: slab-out-of-bounds in uid_eq include/linux/uidgid.h:63 [inline]
BUG: KASAN: slab-out-of-bounds in key_task_permission+0x394/0x410
security/keys/permission.c:54
Read of size 4 at addr ffff88813c3ab618 by task stress-ng/4362

CPU: 2 PID: 4362 Comm: stress-ng Not tainted 5.10.0-14930-gafbffd6c3ede #15
Call Trace:
 __dump_stack lib/dump_stack.c:82 [inline]
 dump_stack+0x107/0x167 lib/dump_stack.c:123
 print_address_description.constprop.0+0x19/0x170 mm/kasan/report.c:400
 __kasan_report.cold+0x6c/0x84 mm/kasan/report.c:560
 kasan_report+0x3a/0x50 mm/kasan/report.c:585
 __kuid_val include/linux/uidgid.h:36 [inline]
 uid_eq include/linux/uidgid.h:63 [inline]
 key_task_permission+0x394/0x410 security/keys/permission.c:54
 search_nested_keyrings+0x90e/0xe90 security/keys/keyring.c:793

This issue was also reported by syzbot.

It can be reproduced by following these steps(more details [1]):
1. Obtain more than 32 inputs that have similar hashes, which ends with the
   pattern '0xxxxxxxe6'.
2. Reboot and add the keys obtained in step 1.

The reproducer demonstrates how this issue happened:
1. In the search_nested_keyrings function, when it iterates through the
   slots in a node(below tag ascend_to_node), if the slot pointer is meta
   and node->back_pointer != NULL(it means a root), it will proceed to
   descend_to_node. However, there is an exception. If node is the root,
   and one of the slots points to a shortcut, it will be treated as a
   keyring.
2. Whether the ptr is keyring decided by keyring_ptr_is_keyring function.
   However, KEYRING_PTR_SUBTYPE is 0x2UL, the same as
   ASSOC_ARRAY_PTR_SUBTYPE_MASK.
3. When 32 keys with the similar hashes are added to the tree, the ROOT
   has keys with hashes that are not similar (e.g. slot 0) and it splits
   NODE A without using a shortcut. When NODE A is filled with keys that
   all hashes are xxe6, the keys are similar, NODE A will split with a
   shortcut. Finally, it forms the tree as shown below, where slot 6 points
   to a shortcut.

                      NODE A
              +------>+---+
      ROOT    |       | 0 | xxe6
      +---+   |       +---+
 xxxx | 0 | shortcut  :   : xxe6
      +---+   |       +---+
 xxe6 :   :   |       |   | xxe6
      +---+   |       +---+
      | 6 |---+       :   : xxe6
      +---+           +---+
 xxe6 :   :           | f | xxe6
      +---+           +---+
 xxe6 | f |
      +---+

4. As mentioned above, If a slot(slot 6) of the root points to a shortcut,
   it may be mistakenly transferred to a key*, leading to a read
   out-of-bounds read.

To fix this issue, one should jump to descend_to_node if the ptr is a
shortcut, regardless of whether the node is root or not.

[1] https://lore.kernel.org/linux-kernel/1cfa878e-8c7b-4570-8606-21daf5e13ce7@huaweicloud.com/

[jarkko: tweaked the commit message a bit to have an appropriate closes
 tag.]
Fixes: b2a4df2 ("KEYS: Expand the capacity of a keyring")
Reported-by: syzbot+5b415c07907a2990d1a3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000cbb7860611f61147@google.com/T/
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
alobakin pushed a commit that referenced this pull request Dec 6, 2024
Shinichiro reported the following use-after free that sometimes is
happening in our CI system when running fstests' btrfs/284 on a TCMU
runner device:

  BUG: KASAN: slab-use-after-free in lock_release+0x708/0x780
  Read of size 8 at addr ffff888106a83f18 by task kworker/u80:6/219

  CPU: 8 UID: 0 PID: 219 Comm: kworker/u80:6 Not tainted 6.12.0-rc6-kts+ #15
  Hardware name: Supermicro Super Server/X11SPi-TF, BIOS 3.3 02/21/2020
  Workqueue: btrfs-endio btrfs_end_bio_work [btrfs]
  Call Trace:
   <TASK>
   dump_stack_lvl+0x6e/0xa0
   ? lock_release+0x708/0x780
   print_report+0x174/0x505
   ? lock_release+0x708/0x780
   ? __virt_addr_valid+0x224/0x410
   ? lock_release+0x708/0x780
   kasan_report+0xda/0x1b0
   ? lock_release+0x708/0x780
   ? __wake_up+0x44/0x60
   lock_release+0x708/0x780
   ? __pfx_lock_release+0x10/0x10
   ? __pfx_do_raw_spin_lock+0x10/0x10
   ? lock_is_held_type+0x9a/0x110
   _raw_spin_unlock_irqrestore+0x1f/0x60
   __wake_up+0x44/0x60
   btrfs_encoded_read_endio+0x14b/0x190 [btrfs]
   btrfs_check_read_bio+0x8d9/0x1360 [btrfs]
   ? lock_release+0x1b0/0x780
   ? trace_lock_acquire+0x12f/0x1a0
   ? __pfx_btrfs_check_read_bio+0x10/0x10 [btrfs]
   ? process_one_work+0x7e3/0x1460
   ? lock_acquire+0x31/0xc0
   ? process_one_work+0x7e3/0x1460
   process_one_work+0x85c/0x1460
   ? __pfx_process_one_work+0x10/0x10
   ? assign_work+0x16c/0x240
   worker_thread+0x5e6/0xfc0
   ? __pfx_worker_thread+0x10/0x10
   kthread+0x2c3/0x3a0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x31/0x70
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1a/0x30
   </TASK>

  Allocated by task 3661:
   kasan_save_stack+0x30/0x50
   kasan_save_track+0x14/0x30
   __kasan_kmalloc+0xaa/0xb0
   btrfs_encoded_read_regular_fill_pages+0x16c/0x6d0 [btrfs]
   send_extent_data+0xf0f/0x24a0 [btrfs]
   process_extent+0x48a/0x1830 [btrfs]
   changed_cb+0x178b/0x2ea0 [btrfs]
   btrfs_ioctl_send+0x3bf9/0x5c20 [btrfs]
   _btrfs_ioctl_send+0x117/0x330 [btrfs]
   btrfs_ioctl+0x184a/0x60a0 [btrfs]
   __x64_sys_ioctl+0x12e/0x1a0
   do_syscall_64+0x95/0x180
   entry_SYSCALL_64_after_hwframe+0x76/0x7e

  Freed by task 3661:
   kasan_save_stack+0x30/0x50
   kasan_save_track+0x14/0x30
   kasan_save_free_info+0x3b/0x70
   __kasan_slab_free+0x4f/0x70
   kfree+0x143/0x490
   btrfs_encoded_read_regular_fill_pages+0x531/0x6d0 [btrfs]
   send_extent_data+0xf0f/0x24a0 [btrfs]
   process_extent+0x48a/0x1830 [btrfs]
   changed_cb+0x178b/0x2ea0 [btrfs]
   btrfs_ioctl_send+0x3bf9/0x5c20 [btrfs]
   _btrfs_ioctl_send+0x117/0x330 [btrfs]
   btrfs_ioctl+0x184a/0x60a0 [btrfs]
   __x64_sys_ioctl+0x12e/0x1a0
   do_syscall_64+0x95/0x180
   entry_SYSCALL_64_after_hwframe+0x76/0x7e

  The buggy address belongs to the object at ffff888106a83f00
   which belongs to the cache kmalloc-rnd-07-96 of size 96
  The buggy address is located 24 bytes inside of
   freed 96-byte region [ffff888106a83f00, ffff888106a83f60)

  The buggy address belongs to the physical page:
  page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888106a83800 pfn:0x106a83
  flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff)
  page_type: f5(slab)
  raw: 0017ffffc0000000 ffff888100053680 ffffea0004917200 0000000000000004
  raw: ffff888106a83800 0000000080200019 00000001f5000000 0000000000000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   ffff888106a83e00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
   ffff888106a83e80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
  >ffff888106a83f00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                              ^
   ffff888106a83f80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
   ffff888106a84000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ==================================================================

Further analyzing the trace and the crash dump's vmcore file shows that
the wake_up() call in btrfs_encoded_read_endio() is calling wake_up() on
the wait_queue that is in the private data passed to the end_io handler.

Commit 4ff47df ("btrfs: move priv off stack in
btrfs_encoded_read_regular_fill_pages()") moved 'struct
btrfs_encoded_read_private' off the stack.

Before that commit one can see a corruption of the private data when
analyzing the vmcore after a crash:

*(struct btrfs_encoded_read_private *)0xffff88815626eec8 = {
	.wait = (wait_queue_head_t){
		.lock = (spinlock_t){
			.rlock = (struct raw_spinlock){
				.raw_lock = (arch_spinlock_t){
					.val = (atomic_t){
						.counter = (int)-2005885696,
					},
					.locked = (u8)0,
					.pending = (u8)157,
					.locked_pending = (u16)40192,
					.tail = (u16)34928,
				},
				.magic = (unsigned int)536325682,
				.owner_cpu = (unsigned int)29,
				.owner = (void *)__SCT__tp_func_btrfs_transaction_commit+0x0 = 0x0,
				.dep_map = (struct lockdep_map){
					.key = (struct lock_class_key *)0xffff8881575a3b6c,
					.class_cache = (struct lock_class *[2]){ 0xffff8882a71985c0, 0xffffea00066f5d40 },
					.name = (const char *)0xffff88815626f100 = "",
					.wait_type_outer = (u8)37,
					.wait_type_inner = (u8)178,
					.lock_type = (u8)154,
				},
			},
			.__padding = (u8 [24]){ 0, 157, 112, 136, 50, 174, 247, 31, 29 },
			.dep_map = (struct lockdep_map){
				.key = (struct lock_class_key *)0xffff8881575a3b6c,
				.class_cache = (struct lock_class *[2]){ 0xffff8882a71985c0, 0xffffea00066f5d40 },
				.name = (const char *)0xffff88815626f100 = "",
				.wait_type_outer = (u8)37,
				.wait_type_inner = (u8)178,
				.lock_type = (u8)154,
			},
		},
		.head = (struct list_head){
			.next = (struct list_head *)0x112cca,
			.prev = (struct list_head *)0x47,
		},
	},
	.pending = (atomic_t){
		.counter = (int)-1491499288,
	},
	.status = (blk_status_t)130,
}

Here we can see several indicators of in-memory data corruption, e.g. the
large negative atomic values of ->pending or
->wait->lock->rlock->raw_lock->val, as well as the bogus spinlock magic
0x1ff7ae32 (decimal 536325682 above) instead of 0xdead4ead or the bogus
pointer values for ->wait->head.

To fix this, change atomic_dec_return() to atomic_dec_and_test() to fix the
corruption, as atomic_dec_return() is defined as two instructions on
x86_64, whereas atomic_dec_and_test() is defined as a single atomic
operation. This can lead to a situation where counter value is already
decremented but the if statement in btrfs_encoded_read_endio() is not
completely processed, i.e. the 0 test has not completed. If another thread
continues executing btrfs_encoded_read_regular_fill_pages() the
atomic_dec_return() there can see an already updated ->pending counter and
continues by freeing the private data. Continuing in the endio handler the
test for 0 succeeds and the wait_queue is woken up, resulting in a
use-after-free.

Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Suggested-by: Damien Le Moal <Damien.LeMoal@wdc.com>
Fixes: 1881fba ("btrfs: add BTRFS_IOC_ENCODED_READ ioctl")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
alobakin pushed a commit that referenced this pull request Feb 21, 2025
While performing the rq locking dance in dispatch_to_local_dsq(), we may
trigger the following lock imbalance condition, in particular when
multiple tasks are rapidly changing CPU affinity (i.e., running a
`stress-ng --race-sched 0`):

[   13.413579] =====================================
[   13.413660] WARNING: bad unlock balance detected!
[   13.413729] 6.13.0-virtme #15 Not tainted
[   13.413792] -------------------------------------
[   13.413859] kworker/1:1/80 is trying to release lock (&rq->__lock) at:
[   13.413954] [<ffffffff873c6c48>] dispatch_to_local_dsq+0x108/0x1a0
[   13.414111] but there are no more locks to release!
[   13.414176]
[   13.414176] other info that might help us debug this:
[   13.414258] 1 lock held by kworker/1:1/80:
[   13.414318]  #0: ffff8b66feb41698 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x20/0x90
[   13.414612]
[   13.414612] stack backtrace:
[   13.415255] CPU: 1 UID: 0 PID: 80 Comm: kworker/1:1 Not tainted 6.13.0-virtme #15
[   13.415505] Workqueue:  0x0 (events)
[   13.415567] Sched_ext: dsp_local_on (enabled+all), task: runnable_at=-2ms
[   13.415570] Call Trace:
[   13.415700]  <TASK>
[   13.415744]  dump_stack_lvl+0x78/0xe0
[   13.415806]  ? dispatch_to_local_dsq+0x108/0x1a0
[   13.415884]  print_unlock_imbalance_bug+0x11b/0x130
[   13.415965]  ? dispatch_to_local_dsq+0x108/0x1a0
[   13.416226]  lock_release+0x231/0x2c0
[   13.416326]  _raw_spin_unlock+0x1b/0x40
[   13.416422]  dispatch_to_local_dsq+0x108/0x1a0
[   13.416554]  flush_dispatch_buf+0x199/0x1d0
[   13.416652]  balance_one+0x194/0x370
[   13.416751]  balance_scx+0x61/0x1e0
[   13.416848]  prev_balance+0x43/0xb0
[   13.416947]  __pick_next_task+0x6b/0x1b0
[   13.417052]  __schedule+0x20d/0x1740

This happens because dispatch_to_local_dsq() is racing with
dispatch_dequeue() and, when the latter wins, we incorrectly assume that
the task has been moved to dst_rq.

Fix by properly tracking the currently locked rq.

Fixes: 4d3ca89 ("sched_ext: Refactor consume_remote_task()")
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
alobakin pushed a commit that referenced this pull request Apr 1, 2025
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>
alobakin pushed a commit that referenced this pull request Apr 3, 2025
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>
alobakin pushed a commit that referenced this pull request Apr 3, 2025
…ge_order()

Patch series "mm: MM owner tracking for large folios (!hugetlb) +
CONFIG_NO_PAGE_MAPCOUNT", v3.

Let's add an "easy" way to decide -- without false positives, without
page-mapcounts and without page table/rmap scanning -- whether a large
folio is "certainly mapped exclusively" into a single MM, or whether it
"maybe mapped shared" into multiple MMs.

Use that information to implement Copy-on-Write reuse, to convert
folio_likely_mapped_shared() to folio_maybe_mapped_share(), and to
introduce a kernel config option that lets us not use+maintain per-page
mapcounts in large folios anymore.

The bigger picture was presented at LSF/MM [1].

This series is effectively a follow-up on my early work [2], which
implemented a more precise, but also more complicated, way to identify
whether a large folio is "mapped shared" into multiple MMs or "mapped
exclusively" into a single MM.


1 Patch Organization
====================

Patch #1 -> #6: make more room in order-1 folios, so we have two
                "unsigned long" available for our purposes

Patch #7 -> #11: preparations

Patch #12: MM owner tracking for large folios

Patch #13: COW reuse for PTE-mapped anon THP

Patch #14: folio_maybe_mapped_shared()

Patch #15 -> #20: introduce and implement CONFIG_NO_PAGE_MAPCOUNT


2 MM owner tracking
===================

We assign each MM a unique ID ("MM ID"), to be able to squeeze more
information in our folios.  On 32bit we use 15-bit IDs, on 64bit we use
31-bit IDs.

For each large folios, we now store two MM-ID+mapcount ("slot")
combinations:
* mm0_id + mm0_mapcount
* mm1_id + mm1_mapcount

On 32bit, we use a 16-bit per-MM mapcount, on 64bit an ordinary 32bit
mapcount.  This way, we require 2x "unsigned long" on 32bit and 64bit for
both slots.

Paired with the large mapcount, we can reliably identify whether one of
these MMs is the current owner (-> owns all mappings) or even holds all
folio references (-> owns all mappings, and all references are from
mappings).

As long as only two MMs map folio pages at a time, we can reliably and
precisely identify whether a large folio is "mapped shared" or "mapped
exclusively".

Any additional MM that starts mapping the folio while there are no free
slots becomes an "untracked MM".  If one such "untracked MM" is the last
one mapping a folio exclusively, we will not detect the folio as "mapped
exclusively" but instead as "maybe mapped shared".  (exception: only a
single mapping remains)

So that's where the approach gets imprecise.

For now, we use a bit-spinlock to sync the large mapcount + slots, and
make sure we do keep the machinery fast, to not degrade (un)map
performance drastically: for example, we make sure to only use a single
atomic (when grabbing the bit-spinlock), like we would already perform
when updating the large mapcount.


3 CONFIG_NO_PAGE_MAPCOUNT
=========================

patch #15 -> #20 spell out and document what exactly is affected when not
maintaining the per-page mapcounts in large folios anymore.

Most importantly, as we cannot maintain folio->_nr_pages_mapped anymore
when (un)mapping pages, we'll account a complete folio as mapped if a
single page is mapped.  In addition, we'll not detect partially mapped
anonymous folios as such in all cases yet.

Likely less relevant changes include that we might now under-estimate the
USS (Unique Set Size) of a process, but never over-estimate it.

The goal is to make CONFIG_NO_PAGE_MAPCOUNT the default at some point, to
then slowly make it the only option, as we learn about real-life impacts
and possible ways to mitigate them.


4 Performance
=============

Detailed performance numbers were included in v1 [3], and not that much
changed between v1 and v2.

I did plenty of measurements on different systems in the meantime, that
all revealed slightly different results.

The pte-mapped-folio micro-benchmarks [4] are fairly sensitive to code
layout changes on some systems.  Especially the fork() benchmark started
being more-shaky-than-before on recent kernels for some reason.

In summary, with my micro-benchmarks:

* Small folios are not impacted.

* CoW performance seems to be mostly unchanged across all folios sizes.

* CoW reuse performance of large folios now matches CoW reuse
  performance of small folios, because we now actually implement the CoW
  reuse optimization.  On an Intel Xeon Silver 4210R I measured a ~65%
  reduction in runtime, on an arm64 system I measured ~54% reduction.

* munmap() performance improves with CONFIG_NO_PAGE_MAPCOUNT.  I saw
  double-digit % reduction (up to ~30% on an Intel Xeon Silver 4210R and
  up to ~70% on an AmpereOne A192-32X) with larger folios.  The larger the
  folios, the larger the performance improvement.

* munmao() performance very slightly (couple percent) degrades without
  CONFIG_NO_PAGE_MAPCOUNT for smaller folios.  For larger folios, there
  seems to be no change at all.

* fork() performance improves with CONFIG_NO_PAGE_MAPCOUNT.  I saw
  double-digit % reduction (up to ~20% on an Intel Xeon Silver 4210R and
  up to ~10% on an AmpereOne A192-32X) with larger folios.  The larger the
  folios, the larger the performance improvement.

* While fork() performance without CONFIG_NO_PAGE_MAPCOUNT seems to be
  almost unchanged on some systems, I saw some degradation for smaller
  folios on the AmpereOne A192-32X.  I did not investigate the details
  yet, but I suspect code layout changes or suboptimal code placement /
  inlining.

I'm not to worried about the fork() micro-benchmarks for smaller folios
given how shaky the results are lately and by how much we improved fork()
performance recently.

I also ran case-anon-cow-rand and case-anon-cow-seq part of
vm-scalability, to assess the scalability and the impact of the
bit-spinlock.  My measurements on a two 2-socket 10-core Intel Xeon Silver
4210R CPU revealed no significant changes.

Similarly, running these benchmarks with 2 MiB THPs enabled on the
AmpereOne A192-32X with 192 cores, I got < 1% difference with < 1% stdev,
which is nice.

So far, I did not get my hands on a similarly large system with multiple
sockets.

I found no other fitting scalability benchmarks that seem to really hammer
on concurrent mapping/unmapping of large folio pages like
case-anon-cow-seq does.


5 Concerns
==========

5.1 Bit spinlock
----------------

I'm not quite happy about the bit-spinlock, but so far it does not seem to
affect scalability in my measurements.

If it ever becomes a problem we could either investigate improving the
locking, or simply stopping the MM tracking once there are "too many
mappings" and simply assume that the folio is "mapped shared" until it was
freed.

This would be similar (but slightly different) to the "0,1,2,stopped"
counting idea Willy had at some point.  Adding that logic to "stop
tracking" adds more code to the hot path, so I avoided that for now.


5.2 folio_maybe_mapped_shared()
-------------------------------

I documented the change from folio_likely_mapped_shared() to
folio_maybe_mapped_shared() quite extensively.  If we run into surprises,
I have some ideas on how to resolve them.  For now, I think we should be
fine.


5.3 Added code to map/unmap hot path
------------------------------------

So far, it looks like the added code on the rmap hot path does not really
seem to matter much in the bigger picture.  I'd like to further reduce it
(and possibly improve fork() performance further), but I don't easily see
how right now.  Well, and I am out of puff 🙂

Having that said, alternatives I considered (e.g., per-MM per-folio
mapcount) would add a lot more overhead to these hot paths.


6 Future Work
=============

6.1 Large mapcount
------------------

It would be very handy if the large mapcount would count how often folio
pages are actually mapped into page tables: a PMD on x86-64 would count
512 times.  Calculating the average per-page mapcount will be easy, and
remapping (PMD->PTE) folios would get even faster.

That would also remove the need for the entire mapcount (except for
PMD-sized folios for memory statistics reasons ...), and allow for mapping
folios larger than PMDs (e.g., 4 MiB) easily.

We likely would also have to take the same number of folio references to
make our folio_mapcount() == folio_ref_count() work, and we'd want to be
able to avoid mapcount+refcount overflows: this could already become an
issue with pte-mapped PUD-sized folios (fsdax).

One approach we discussed in the THP cabal meeting is (1) extending the
mapcount for large folios to 64bit (at least on 64bit systems) and (2)
keeping the refcount at 32bit, but (3) having exactly one reference if the
the mapcount != 0.

It should be doable, but there are some corner cases to consider on the
unmap path; it is something that I will be looking into next.


6.2 hugetlb
-----------

I'd love to make use of the same tracking also for hugetlb.

The real problem is PMD table sharing: getting a page mapped by MM X and
unmapped by MM Y will not work.  With mshare, that problem should not
exist (all mapping/unmapping will be routed through the mshare MM).

[1] https://lwn.net/Articles/974223/
[2] https://lore.kernel.org/linux-mm/a9922f58-8129-4f15-b160-e0ace581bcbe@redhat.com/T/
[3] https://lkml.kernel.org/r/20240829165627.2256514-1-david@redhat.com
[4] https://gitlab.com/davidhildenbrand/scratchspace/-/raw/main/pte-mapped-folio-benchmarks.c


This patch (of 20):

Let's factor it out into a simple helper function.  This helper will also
come in handy when working with code where we know that our folio is
large.

Maybe in the future we'll have the order readily available for small and
large folios; in that case, folio_large_order() would simply translate to
folio_order().

Link: https://lkml.kernel.org/r/20250303163014.1128035-1-david@redhat.com
Link: https://lkml.kernel.org/r/20250303163014.1128035-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lance Yang <ioworker0@gmail.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirks^H^Hski <luto@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcow (Oracle) <willy@infradead.org>
Cc: Michal Koutn <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: tejun heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
alobakin pushed a commit that referenced this pull request May 12, 2025
Ido Schimmel says:

====================
vxlan: Convert FDB table to rhashtable

The VXLAN driver currently stores FDB entries in a hash table with a
fixed number of buckets (256), resulting in reduced performance as the
number of entries grows. This patchset solves the issue by converting
the driver to use rhashtable which maintains a more or less constant
performance regardless of the number of entries.

Measured transmitted packets per second using a single pktgen thread
with varying number of entries when the transmitted packet always hits
the default entry (worst case):

Number of entries | Improvement
------------------|------------
1k                | +1.12%
4k                | +9.22%
16k               | +55%
64k               | +585%
256k              | +2460%

The first patches are preparations for the conversion in the last patch.
Specifically, the series is structured as follows:

Patch #1 adds RCU read-side critical sections in the Tx path when
accessing FDB entries. Targeting at net-next as I am not aware of any
issues due to this omission despite the code being structured that way
for a long time. Without it, traces will be generated when converting
FDB lookup to rhashtable_lookup().

Patch #2-#5 simplify the creation of the default FDB entry (all-zeroes).
Current code assumes that insertion into the hash table cannot fail,
which will no longer be true with rhashtable.

Patches #6-#10 add FDB entries to a linked list for entry traversal
instead of traversing over them using the fixed size hash table which is
removed in the last patch.

Patches #11-#12 add wrappers for FDB lookup that make it clear when each
should be used along with lockdep annotations. Needed as a preparation
for rhashtable_lookup() that must be called from an RCU read-side
critical section.

Patch #13 treats dst cache initialization errors as non-fatal. See more
info in the commit message. The current code happens to work because
insertion into the fixed size hash table is slow enough for the per-CPU
allocator to be able to create new chunks of per-CPU memory.

Patch #14 adds an FDB key structure that includes the MAC address and
source VNI. To be used as rhashtable key.

Patch #15 does the conversion to rhashtable.
====================

Link: https://patch.msgid.link/20250415121143.345227-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
alobakin pushed a commit that referenced this pull request Jun 18, 2025
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>
alobakin pushed a commit that referenced this pull request Jul 25, 2025
The 'icc_bw_lock' mutex is introduced in commit af42269
("interconnect: Fix locking for runpm vs reclaim") in order to decouple
serialization of bw aggregation from codepaths that require memory
allocation.

However commit d30f83d ("interconnect: core: Add dynamic id
allocation support") added a devm_kasprintf() call into a path protected
by the 'icc_bw_lock' which causes the following lockdep warning on
machines like the Lenovo ThinkPad X13s:

    ======================================================
    WARNING: possible circular locking dependency detected
    6.16.0-rc3 #15 Not tainted
    ------------------------------------------------------
    (udev-worker)/342 is trying to acquire lock:
    ffffb973f7ec4638 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_node_track_caller_noprof+0xa0/0x3e0

    but task is already holding lock:
    ffffb973f7f7f0e8 (icc_bw_lock){+.+.}-{4:4}, at: icc_node_add+0x44/0x154

    which lock already depends on the new lock.

    the existing dependency chain (in reverse order) is:

    -> #1 (icc_bw_lock){+.+.}-{4:4}:
           icc_init+0x48/0x108
           do_one_initcall+0x64/0x30c
           kernel_init_freeable+0x27c/0x500
           kernel_init+0x20/0x1d8
           ret_from_fork+0x10/0x20

    -> #0 (fs_reclaim){+.+.}-{0:0}:
           __lock_acquire+0x136c/0x2114
           lock_acquire+0x1c8/0x354
           fs_reclaim_acquire+0x74/0xa8
           __kmalloc_node_track_caller_noprof+0xa0/0x3e0
           devm_kmalloc+0x54/0x124
           devm_kvasprintf+0x74/0xd4
           devm_kasprintf+0x58/0x80
           icc_node_add+0xb4/0x154
           qcom_osm_l3_probe+0x20c/0x314 [icc_osm_l3]
           platform_probe+0x68/0xd8
           really_probe+0xc0/0x38c
           __driver_probe_device+0x7c/0x160
           driver_probe_device+0x40/0x110
           __driver_attach+0xfc/0x208
           bus_for_each_dev+0x74/0xd0
           driver_attach+0x24/0x30
           bus_add_driver+0x110/0x234
           driver_register+0x60/0x128
           __platform_driver_register+0x24/0x30
           osm_l3_driver_init+0x20/0x1000 [icc_osm_l3]
           do_one_initcall+0x64/0x30c
           do_init_module+0x58/0x23c
           load_module+0x1df8/0x1f70
           init_module_from_file+0x88/0xc4
           idempotent_init_module+0x188/0x280
           __arm64_sys_finit_module+0x6c/0xd8
           invoke_syscall+0x48/0x110
           el0_svc_common.constprop.0+0xc0/0xe0
           do_el0_svc+0x1c/0x28
           el0_svc+0x4c/0x158
           el0t_64_sync_handler+0xc8/0xcc
           el0t_64_sync+0x198/0x19c

    other info that might help us debug this:

     Possible unsafe locking scenario:

           CPU0                    CPU1
           ----                    ----
      lock(icc_bw_lock);
                                   lock(fs_reclaim);
                                   lock(icc_bw_lock);
      lock(fs_reclaim);

     *** DEADLOCK ***

The icc_node_add() functions is not designed to fail, and as such it
should not do any memory allocation. In order to avoid this, add a new
helper function for the name generation to be called by drivers which
are using the new dynamic id feature.

Fixes: d30f83d ("interconnect: core: Add dynamic id allocation support")
Signed-off-by: Gabor Juhos <j4g8y7@gmail.com>
Link: https://lore.kernel.org/r/20250625-icc-bw-lockdep-v3-1-2b8f8b8987c4@gmail.com
Co-developed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20250627075854.26943-1-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
alobakin pushed a commit that referenced this pull request Aug 4, 2025
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>
alobakin pushed a commit that referenced this pull request Aug 4, 2025
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>
alobakin pushed a commit that referenced this pull request Aug 8, 2025
Use BPF_TRAMP_F_INDIRECT flag to detect struct ops and emit proper
prologue and epilogue for this case.

With this patch, all of the struct_ops related testcases (except
struct_ops_multi_pages) passed on LoongArch.

The testcase struct_ops_multi_pages failed is because the actual
image_pages_cnt is 40 which is bigger than MAX_TRAMP_IMAGE_PAGES.

Before:

  $ sudo ./test_progs -t struct_ops -d struct_ops_multi_pages
  ...
  WATCHDOG: test case struct_ops_module/struct_ops_load executes for 10 seconds...

After:

  $ sudo ./test_progs -t struct_ops -d struct_ops_multi_pages
  ...
  #15      bad_struct_ops:OK
  ...
  torvalds#399     struct_ops_autocreate:OK
  ...
  torvalds#400     struct_ops_kptr_return:OK
  ...
  torvalds#401     struct_ops_maybe_null:OK
  ...
  torvalds#402     struct_ops_module:OK
  ...
  torvalds#404     struct_ops_no_cfi:OK
  ...
  torvalds#405     struct_ops_private_stack:SKIP
  ...
  torvalds#406     struct_ops_refcounted:OK
  Summary: 8/25 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
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3 participants