md: move revalidate_disk() back outside open_mutex

Commit b821eaa5 "md: remove ->changed and related code" moved
revalidate_disk() under open_mutex, and lockdep noticed.

[ INFO: possible circular locking dependency detected ]
2.6.32-mdadm-locking #1
-------------------------------------------------------
mdadm/3640 is trying to acquire lock:
 (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff811acecb>] revalidate_disk+0x5b/0x90

but task is already holding lock:
 (&mddev->open_mutex){+.+...}, at: [<ffffffffa055e07a>] do_md_stop+0x4a/0x4d0 [md_mod]

which lock already depends on the new lock.

It is suitable for 2.6.35.x

Cc: <[email protected]>
Reported-by: Przemyslaw Czarnowski <[email protected]>
Signed-off-by: Dan Williams <[email protected]>
Signed-off-by: NeilBrown <[email protected]>
This commit is contained in:
Dan Williams 2010-08-06 18:01:59 -07:00 • committed by NeilBrown
commit 147e0b6a63

View file

@ -4765,7 +4765,7 @@ out:
*/
static int do_md_stop(mddev_t * mddev, int mode, int is_open)
{
int err = 0;
int err = 0, revalidate = 0;
struct gendisk *disk = mddev->gendisk;
mdk_rdev_t *rdev;
@ -4795,7 +4795,7 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
}
set_capacity(disk, 0);
revalidate_disk(disk);
revalidate = 1;
if (mddev->ro)
mddev->ro = 0;
@ -4803,6 +4803,8 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
err = 0;
}
mutex_unlock(&mddev->open_mutex);
if (revalidate)
revalidate_disk(disk);
if (err)
return err;
/*