[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Yury Selivanov added the comment: Thank you so much, Stefan, for looking into this. Really appreciate the help. -- ___ Python tracker ___ _

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Evgeny Boytsov added the comment: I checked both my test example and real production code with your patch. I'm unable to reproduce the bug, so I think it is fixed now. Thank you! -- ___ Python tracker _

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Stefan Krah added the comment: Thanks Ned, closing then. Evgeny, please reopen if you see it again (I ran the tests for about 20 min, way above the usual reproduction time of 1 min). Thanks for the very instructive test case! -- status: open -> closed __

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Ned Deily added the comment: Thanks for the heads-up and the fix, Stefan. The fix for 3.7.x was merged before the 3.7.7rc1 cutoff (by a few hours!) and the next 3.8.x release cutoff is planned for April and 3.9.0a5 is later in March, so, if you are not planning to merge any other changes for

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Change by Stefan Krah : -- resolution: -> fixed ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Change by Stefan Krah : -- stage: patch review -> resolved ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: ht

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Stefan Krah added the comment: Setting to release blocker, but please move to deferred again if a release is almost finished. -- nosy: +lukasz.langa, ned.deily priority: deferred blocker -> release blocker ___ Python tracker

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Stefan Krah added the comment: Also _pydecimal was affected. This is a modified version of Evgeny's test case: from _pydecimal import * from time import sleep from random import randint import sys sys.setswitchinterval(0.001) def usleep(x): sleep(x/100.0) class Test: def

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Change by Stefan Krah : Added file: https://bugs.python.org/file48945/pydecimal_cases.zip ___ Python tracker ___ ___ Python-bugs-list mailin

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Stefan Krah added the comment: Since many duplicate tstate ids are generated in the test case before the crash happens, I guess a set of tstates with the same id silently uses the cached context of the "winner" tstate. This can lead to incorrect results without noticing. -- priority:

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Change by Stefan Krah : -- assignee: -> skrah ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.p

[issue39776] PyContextVar_Get(): crash due to race condition in updating tstate->id

Change by Stefan Krah : -- title: Crash in decimal module in heavy-multithreaded scenario -> PyContextVar_Get(): crash due to race condition in updating tstate->id ___ Python tracker