Bug report
Bug description:
A TSAN (gcc-12) build of the latest version of cpython reports a race in the test_send_recv_different_interpreters_and_threads test:
Read of size 4 at 0x7ffe8d0c9338 by main thread:
#0 _waiting_finish_releasing Modules/_interpchannelsmodule.c:504 (_interpchannels.cpython-314-x86_64-linux-gnu.so+0x88f4) (BuildId: 233ea3cec8e2d6b4a5322cdab2aa3fcc24ab85f8)
#1 channel_send_wait Modules/_interpchannelsmodule.c:1852 (_interpchannels.cpython-314-x86_64-linux-gnu.so+0x88f4)
#2 channelsmod_send Modules/_interpchannelsmodule.c:3096 (_interpchannels.cpython-314-x86_64-linux-gnu.so+0x8dd0) (BuildId: 233ea3cec8e2d6b4a5322cdab2aa3fcc24ab85f8)
#3 cfunction_call Objects/methodobject.c:540 (python+0x549e55) (BuildId: f667f6a4a823ca3db627f9e7bf3836f7af978c6d)
#0 _waiting_release Modules/_interpchannelsmodule.c:498 (_interpchannels.cpython-314-x86_64-linux-gnu.so+0x37c7) (BuildId: 233ea3cec8e2d6b4a5322cdab2aa3fcc24ab85f8)
#1 channel_recv Modules/_interpchannelsmodule.c:1937 (_interpchannels.cpython-314-x86_64-linux-gnu.so+0x863a) (BuildId: 233ea3cec8e2d6b4a5322cdab2aa3fcc24ab85f8)
#2 channelsmod_recv Modules/_interpchannelsmodule.c:3189 (_interpchannels.cpython-314-x86_64-linux-gnu.so+0x863a)
Indeed,
|
while (waiting->status == WAITING_RELEASING) { |
spin waits for
waiting->status to change state, with
|
waiting->status = WAITING_RELEASED; |
triggering the spinning thread to exit the spin. Neither happens under a mutex, or with any release-acquire sequencing.
CPython versions tested on:
CPython main branch
Operating systems tested on:
Linux
Linked PRs
Bug report
Bug description:
A TSAN (gcc-12) build of the latest version of cpython reports a race in the test_send_recv_different_interpreters_and_threads test:
Indeed,
cpython/Modules/_interpchannelsmodule.c
Line 504 in 8b209fd
waiting->statusto change state, withcpython/Modules/_interpchannelsmodule.c
Line 498 in 8b209fd
CPython versions tested on:
CPython main branch
Operating systems tested on:
Linux
Linked PRs
_interpchannels._waiting_release(GH-124107) #139517