diff options
| author | NeilBrown <neilb@suse.de> | 2009-12-14 12:49:46 +1100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-12-18 14:04:11 -0800 |
| commit | f1416ea0278b4bb6629d160e81e61ef8b6bffb4a (patch) | |
| tree | 39b10d44c8d8f157f78af24689459e5a1cb55ee0 /drivers/md/md.c | |
| parent | e4f676cea796e170fcd8561c8e2a234724d05f35 (diff) | |
md/bitmap: protect against bitmap removal while being updated.
commit aa5cbd103887011b4830355f88fb055f9ad2d556 upstream.
A write intent bitmap can be removed from an array while the
array is active.
When this happens, all IO is suspended and flushed before the
bitmap is removed.
However it is possible that bitmap_daemon_work is still running to
clear old bits from the bitmap. If it is, it can dereference the
bitmap after it has been freed.
So introduce a new mutex to protect bitmap_daemon_work and get it
before destroying a bitmap.
This is suitable for any current -stable kernel.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/md/md.c')
| -rw-r--r-- | drivers/md/md.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index b182f86a19dd..02e45513789b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -367,6 +367,7 @@ static mddev_t * mddev_find(dev_t unit) mutex_init(&new->open_mutex); mutex_init(&new->reconfig_mutex); + mutex_init(&new->bitmap_mutex); INIT_LIST_HEAD(&new->disks); INIT_LIST_HEAD(&new->all_mddevs); init_timer(&new->safemode_timer); @@ -6629,7 +6630,7 @@ void md_check_recovery(mddev_t *mddev) if (mddev->bitmap) - bitmap_daemon_work(mddev->bitmap); + bitmap_daemon_work(mddev); if (mddev->ro) return; |