blk-cgroup: use GFP_NOIO for radix tree preload in blkg_conf_prep - #1244
Open
blktests-ci-kpd[bot] wants to merge 1 commit into
Open
blk-cgroup: use GFP_NOIO for radix tree preload in blkg_conf_prep#1244blktests-ci-kpd[bot] wants to merge 1 commit into
blktests-ci-kpd[bot] wants to merge 1 commit into
Conversation
Author
|
Upstream branch: ba285ed Pull request is NOT updated. Failed to apply https://patchwork.kernel.org/series/1154151/ conflict: |
Author
|
Upstream branch: ba285ed |
blktests-ci-kpd
Bot
force-pushed
the
series/1154151=>for-next
branch
from
September 8, 2026 15:50
56a8c44 to
bec1bc2
Compare
blktests-ci-kpd
Bot
force-pushed
the
for-next_base
branch
from
September 9, 2026 07:40
a7792e9 to
d7f8d66
Compare
Author
|
Upstream branch: dd660a0 |
blktests-ci-kpd
Bot
force-pushed
the
series/1154151=>for-next
branch
from
September 9, 2026 08:11
bec1bc2 to
1938e1a
Compare
blktests-ci-kpd
Bot
force-pushed
the
for-next_base
branch
from
September 10, 2026 15:29
d7f8d66 to
60818a6
Compare
Author
|
Upstream branch: 9dcbf66 |
blktests-ci-kpd
Bot
force-pushed
the
series/1154151=>for-next
branch
from
September 10, 2026 16:01
1938e1a to
a6f3589
Compare
blktests-ci-kpd
Bot
force-pushed
the
for-next_base
branch
from
September 12, 2026 02:26
60818a6 to
ddf8681
Compare
blkg_conf_prep() allocates a new blkg with GFP_NOIO after dropping queue_lock, but still preloads the radix tree node with GFP_KERNEL while q->blkcg_mutex is held. GFP_KERNEL may enter direct reclaim and acquire fs_reclaim, which adds the dependency q->blkcg_mutex -> fs_reclaim This completes a circular locking dependency with the existing path fs_reclaim -> q->q_usage_counter -> q->blkcg_mutex and triggers a lockdep warning when configuring blkcg policies. Use GFP_NOIO for radix_tree_preload() so that the preload context matches the rest of this allocation path and does not recurse into reclaim while q->blkcg_mutex is held. Reported-by: syzbot+144a1c0e22e53a08ef5a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=144a1c0e22e53a08ef5a Fixes: f255c19 ("blk-cgroup: Pre-allocate tree node on blkg_conf_prep") Cc: stable@vger.kernel.org Signed-off-by: Tao Yu <tao1.yu@intel.com>
Author
|
Upstream branch: ab5dc9d |
blktests-ci-kpd
Bot
force-pushed
the
series/1154151=>for-next
branch
from
September 12, 2026 02:58
a6f3589 to
84dddcc
Compare
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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.
Pull request for series with
subject: blk-cgroup: use GFP_NOIO for radix tree preload in blkg_conf_prep
version: 1
url: https://patchwork.kernel.org/series/1154151/