Re: 2.6.20-rc3-mm1 - git-block.patch causes hard lockups

[Jens Axboe <jens.axboe@oracle.com>]

On Sat, Jan 06 2007, Valdis.Kletnieks@vt.edu wrote:
> On Thu, 04 Jan 2007 22:02:00 PST, Andrew Morton said:
> 
> > 	ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.20-rc3/2.6.20-rc3-mm1/
> 
> With git-block.patch applied, my system locks up *hard* at system
> shutdown time - even alt-sysrq doesn't do anything.  Need to do the
> "power button for 5" stunt to get the system back.

Does this change anything?

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index ec40e44..bae57e0 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -1542,7 +1542,7 @@ static inline void queue_sync_plugs(request_queue_t *q)
 	 * If the current process is plugged and has barriers submitted,
 	 * we will livelock if we don't unplug first.
 	 */
-	blk_unplug_current();
+	blk_replug_current_nested();
 
 	synchronize_qrcu(&q->qrcu);
 }

-- 
Jens Axboe