erofs: fix PSI memstall accounting

Max Kellermann recently reported psi_group_cpu.tasks[NR_MEMSTALL] is
incorrect in the 6.11.9 kernel.

The root cause appears to be that, since the problematic commit, bio
can be NULL, causing psi_memstall_leave() to be skipped in
z_erofs_submit_queue().

Reported-by: Max Kellermann <max.kellermann@ionos.com>
Closes: https://lore.kernel.org/r/CAKPOu+8tvSowiJADW2RuKyofL_CSkm_SuyZA7ME5vMLWmL6pqw@mail.gmail.com
Fixes: 9e2f9d34dd ("erofs: handle overlapped pclusters out of crafted images properly")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241127085236.3538334-1-hsiangkao@linux.alibaba.com
This commit is contained in:
Gao Xiang 2024-11-27 16:52:36 +08:00
parent b10a1e5643
commit 1a2180f685

View File

@ -1792,9 +1792,9 @@ drain_io:
erofs_fscache_submit_bio(bio);
else
submit_bio(bio);
if (memstall)
psi_memstall_leave(&pflags);
}
if (memstall)
psi_memstall_leave(&pflags);
/*
* although background is preferred, no one is pending for submission.