This is a note to let you know that I've just added the patch titled
dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dm-set-dmf_suspended-_before_-clearing-dmf_noflush_suspending.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From eaf9a7361f47727b166688a9f2096854eef60fbe Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@xxxxxxxxxx>
Date: Tue, 2 Aug 2016 13:07:20 -0400
Subject: dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING
From: Mike Snitzer <snitzer@xxxxxxxxxx>
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 <bart.vanassche@xxxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/dm.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -3078,7 +3078,8 @@ static void unlock_fs(struct mapped_devi
* 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_de
* 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
* 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);
}
Patches currently in stable-queue which might be from snitzer@xxxxxxxxxx are
queue-4.4/dm-set-dmf_suspended-_before_-clearing-dmf_noflush_suspending.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html