From: Mike Snitzer Date: Tue, 2 Aug 2016 17:07:20 +0000 (-0400) Subject: dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING X-Git-Tag: Ubuntu-snapdragon-4.4.0-1029.32~982 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=5616edda43378e67447437aab01c075d6ef9d9c2;p=mirror_ubuntu-zesty-kernel.git dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING BugLink: http://bugs.launchpad.net/bugs/1615620 commit eaf9a7361f47727b166688a9f2096854eef60fbe upstream. Otherwise, there is potential for both DMF_SUSPENDED* and DMF_NOFLUSH_SUSPENDING to not be set during dm_suspend() -- which is definitely _not_ a valid state. This fix, in conjuction with "dm rq: fix the starting and stopping of blk-mq queues", addresses the potential for request-based DM multipath's __multipath_map() to see !dm_noflush_suspending() during suspend. Reported-by: Bart Van Assche Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman Signed-off-by: Tim Gardner Signed-off-by: Kamal Mostafa --- diff --git a/drivers/md/dm.c b/drivers/md/dm.c index c338aebb4ccd..a42729ebf272 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -3078,7 +3078,8 @@ static void unlock_fs(struct mapped_device *md) * Caller must hold md->suspend_lock */ static int __dm_suspend(struct mapped_device *md, struct dm_table *map, - unsigned suspend_flags, int interruptible) + unsigned suspend_flags, int interruptible, + int dmf_suspended_flag) { bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; @@ -3145,6 +3146,8 @@ static int __dm_suspend(struct mapped_device *md, struct dm_table *map, * to finish. */ r = dm_wait_for_completion(md, interruptible); + if (!r) + set_bit(dmf_suspended_flag, &md->flags); if (noflush) clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); @@ -3206,12 +3209,10 @@ retry: map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); - r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE); + r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE, DMF_SUSPENDED); if (r) goto out_unlock; - set_bit(DMF_SUSPENDED, &md->flags); - dm_table_postsuspend_targets(map); out_unlock: @@ -3305,9 +3306,8 @@ static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_fla * would require changing .presuspend to return an error -- avoid this * until there is a need for more elaborate variants of internal suspend. */ - (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE); - - set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); + (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE, + DMF_SUSPENDED_INTERNALLY); dm_table_postsuspend_targets(map); }