Re: [PATCH -next] md/raid10: fix a 'conf->barrier' leakage in raid10_takeover()
From: Paul Menzel <hidden>
Date: 2023-07-31 05:50:35
Also in:
lkml
Dear Yu, Thank you for your patch. Some minor style comments for the commit message, you can also ignore. Am 31.07.23 um 04:28 schrieb Yu Kuai:
From: Yu Kuai <redacted>
After commit 4d27e927344a ("md: don't quiesce in mddev_suspend()"),
'conf->barrier' will be leaked in the case that raid10 takeover raid0:
level_store
pers->takeover -> raid10_takeover
raid10_takeover_raid0
WRITE_ONCE(conf->barrier, 1)
mddev_suspend
// still raid0
mddev->pers = pers
// switch to raid10
mddev_resume
// resume without suspend
After the above commit, mddev_resume() will not decrease 'conf->barrier'
that is set in raid10_takeover_raid0().
Fix this problem by remove the setting of 'conf->barrier' fromremoving or … by not setting `conf->barrier` in …
raid10_takeover_raid0(). By the way, this problem is found while I'm trying to make mddev_suspend/resume() to be independent from raid personalities. rai10
rai*d*
quoted hunk ↗ jump to hunk
is the only personality to use reference count in the quiesce() callback and this problem is only related to raid10. Fixes: 4d27e927344a ("md: don't quiesce in mddev_suspend()") Signed-off-by: Yu Kuai <redacted> --- drivers/md/raid10.c | 1 - 1 file changed, 1 deletion(-)diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 16aa9d735880..7704a4c7f469 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c@@ -4417,7 +4417,6 @@ static void *raid10_takeover_raid0(struct mddev *mddev, sector_t size, int devs) rdev->new_raid_disk = rdev->raid_disk * 2; rdev->sectors = size; } - WRITE_ONCE(conf->barrier, 1); } return conf;
Reviewed-by: Paul Menzel <redacted> Kind regards, Paul