Curiously, I couldn't find any relevant crashes on the KMSAN syzbot instance, but the issue is legit. Thank you so much for fixing this!
Any chance you can add a test case for it to mm/kmsan/kmsan_test.c?
Unfortunately most of the KMSAN test cases already fail on upstream, which makes it difficult to develop new ones:
The KMSAN test failures bisect to the following commit:
commit f90b474a35744b5d43009e4fab232e74a3024cae Author: Vlastimil Babka <vbabka@suse.cz> Date: Mon Mar 10 13:40:17 2025 +0100 mm: Fix the flipped condition in gfpflags_allow_spinning()I'm not sure why. Apparently something related to lib/stackdepot.c.
Reverting that commit on top of upstream fixes the KMSAN tests.
Rolling back all the BPF (?) related changes that were made to lib/stackdepot.c in v6.15 fixes this too. Looks like there was a regression where stack traces stopped being saved in some cases.
Hmm, the tests don't fail for me on v6.17-rc5 with the attached config. Could you share yours?