Fix parallel use of not thread-safe SubtitleFormat instance #13384
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
1 task
35e17be to
088fb64
Compare
|
I've tested this using the reproduction steps (with media containing 2 external srt subtitle files) and using chromecast on a wide range of content (that had problems in the past) and so far I haven't found any issues with subtitles. |
gnattu
approved these changes
Jan 17, 2025
|
Probably targeting 10.10 and backport to master would be better |
|
I confirm that it solves the issues with several media that had the problem before, mainly mkv with several sub tracks. |
|
@gnattu Changed the base branch to release-10.10.z. |
`SubtitleFormat`'s `LoadSubtitle()` function is not thread-safe. A `SubtitleEditParser` instance's `Parse()` function can be called from multiple threads at the same time. `SubtitleFormat`s are cached in the constructor of each `SubtitleEditParser`, and the same instances are used for each possibly parallel `Parse()` function call, which causes subtitle parse problems. This patch modifies the code, so we only cache the extension -> `SubtitleFormat` type/class mapping and create a new `SubtitleFormat` instance in each `Parse()` call, so no `SubtitleFormat` instance is accessed from multiple threads. Fixes jellyfin#12113 Kudos for everyone investigating the issue there, most notably @RenV123 for PoC-ing the solution. Signed-off-by: Attila Szakacs <szakacs.attila96@gmail.com>
088fb64 to
c693da9
Compare
Shadowghost
approved these changes
Jan 18, 2025
0b2a59e
into
jellyfin:release-10.10.z
18 of 19 checks passed
Bond-009
pushed a commit
that referenced
this pull request
Feb 3, 2025
Fix parallel use of not thread-safe SubtitleFormat instance Original-merge: 0b2a59e Merged-by: joshuaboniface <joshua@boniface.me> Backported-by: Bond_009 <bond.009@outlook.com>
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Changes
SubtitleFormat'sLoadSubtitle()function is not thread-safe.A
SubtitleEditParserinstance'sParse()function can be called from multiple threads at the same time.SubtitleFormats are cached in the constructor of eachSubtitleEditParser, and the same instances are used for each possibly parallelParse()function call, which causes subtitle parse problems.This patch modifies the code, so we only cache the extension ->
SubtitleFormattype/class mapping and create a newSubtitleFormatinstance in eachParse()call, so noSubtitleFormatinstance is accessed from multiple threads.Issues
Fixes #12113
Kudos for everyone investigating the issue there, most notably @RenV123 for PoC-ing the solution.