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| author | Denis Efremov <yefremov.denis@gmail.com> | 2012-10-11 04:08:02 +0200 |
|---|---|---|
| committer | NeilBrown <neilb@suse.de> | 2012-10-11 04:08:02 +0200 |
| commit | bc78c57388e7f447f58e30d60b1505ddaaaf3a7d (patch) | |
| tree | 05257b01ee452d05490de4a2d434163b0838be74 /drivers/md/linear.c | |
| parent | block: makes bio_split support bio without data (diff) | |
| download | linux-bc78c57388e7f447f58e30d60b1505ddaaaf3a7d.tar.xz linux-bc78c57388e7f447f58e30d60b1505ddaaaf3a7d.zip | |
md/linear: rcu_dereference outside read-lock section
According to the comment in linear_stop function
rcu_dereference in linear_start and linear_stop functions
occurs under reconfig_mutex. The patch represents this
agreement in code and prevents lockdep complaint.
Found by Linux Driver Verification project (linuxtesting.org)
Signed-off-by: Denis Efremov <yefremov.denis@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'drivers/md/linear.c')
| -rw-r--r-- | drivers/md/linear.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/md/linear.c b/drivers/md/linear.c index fa211d80fc0a..92c64d162a92 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -244,7 +244,9 @@ static int linear_add(struct mddev *mddev, struct md_rdev *rdev) if (!newconf) return -ENOMEM; - oldconf = rcu_dereference(mddev->private); + oldconf = rcu_dereference_protected(mddev->private, + lockdep_is_held( + &mddev->reconfig_mutex)); mddev->raid_disks++; rcu_assign_pointer(mddev->private, newconf); md_set_array_sectors(mddev, linear_size(mddev, 0, 0)); @@ -256,7 +258,10 @@ static int linear_add(struct mddev *mddev, struct md_rdev *rdev) static int linear_stop (struct mddev *mddev) { - struct linear_conf *conf = mddev->private; + struct linear_conf *conf = + rcu_dereference_protected(mddev->private, + lockdep_is_held( + &mddev->reconfig_mutex)); /* * We do not require rcu protection here since |