gh-140431: Fix GC crash due to partially initialized coroutines#140470
Uh oh!
There was an error while loading. Please reload this page.
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
The `make_gen()` function creates and tracks generator/coro objects, but doesn't fully initialize all the fields. At a minimum, we need to initialize all the fields that may be accessed by gen_traverse because the call to `compute_cr_origin()` can trigger a GC.
Contributor
For what it's worth, with this patch, I am no longer able to reproduce the bug. With this patch, I was not able to reproduce the bug after an hour of running the tests. Without this patch, the segfault occurs on average after < 4 minutes. I have used the following script to check: Details#!/usr/bin/env bashset -e time_start=$(date +%s) git clean -dfx CC=clang CXX=clang++ ./configure --with-address-sanitizer --with-pydebug --disable-gil make -j12 ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading ./python -X dev -m test -R 9:9 test_asyncio.test_free_threading time_end=$(date +%s) delta=$((time_end - time_start)) minutes=$((delta /60)) seconds=$((delta %60))echoechoecho"Elapsed time: ${minutes}m ${seconds}s"echoecho -n "Possibly good commit: " git rev-parse HEAD git log --oneline | head -n 1 echo |
efimov-mikhail approved these changes Oct 23, 2025
Member
efimov-mikhail left a comment
efimov-mikhail left a comment There was a problem hiding this comment.
LGTM.
We definitely need to set correct value of gen->gi_iframe.f_executable in make_gen.
colesbury merged commit 574405c into python:main 53 checks passed
Uh oh!
There was an error while loading. Please reload this page.
Thanks @colesbury for the PR 🌮🎉.. I'm working now to backport this PR to: 3.14. |
miss-islington pushed a commit to miss-islington/cpython that referenced this pull request Oct 23, 2025
…pythongh-140470) The `make_gen()` function creates and tracks generator/coro objects, but doesn't fully initialize all the fields. At a minimum, we need to initialize all the fields that may be accessed by gen_traverse because the call to `compute_cr_origin()` can trigger a GC. (cherry picked from commit 574405c) Co-authored-by: Sam Gross <colesbury@gmail.com>
GH-140504 is a backport of this pull request to the 3.14 branch. |
bedevere-bot commented Oct 23, 2025
|
colesbury added a commit that referenced this pull request Oct 23, 2025
gh-140470) (gh-140504) The `make_gen()` function creates and tracks generator/coro objects, but doesn't fully initialize all the fields. At a minimum, we need to initialize all the fields that may be accessed by gen_traverse because the call to `compute_cr_origin()` can trigger a GC. (cherry picked from commit 574405c) Co-authored-by: Sam Gross <colesbury@gmail.com>
StanFromIreland pushed a commit to StanFromIreland/cpython that referenced this pull request Dec 6, 2025
…pythongh-140470) The `make_gen()` function creates and tracks generator/coro objects, but doesn't fully initialize all the fields. At a minimum, we need to initialize all the fields that may be accessed by gen_traverse because the call to `compute_cr_origin()` can trigger a GC.
Sign up for freeto join this conversation on GitHub. Already have an account? Sign in to comment
5 participants
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.
The
make_gen()function creates and tracks generator/coro objects, but doesn't fully initialize all the fields. At a minimum, we need to initialize all the fields that may be accessed by gen_traverse because the call tocompute_cr_origin()can trigger a GC.