Commit 1850753d authored Jul 03, 2012 by majianpeng Committed by NeilBrown Jul 03, 2012

md/raid5: In ops_run_io, inc nr_pending before calling md_wait_for_blocked_rdev



In ops_run_io(), the call to md_wait_for_blocked_rdev will decrement
nr_pending so we lose the reference we hold on the rdev.
So atomic_inc it first to maintain the reference.

This bug was introduced by commit  73e92e51
    md/raid5.  Don't write to known bad block on doubtful devices.

which appeared in 3.0, so patch is suitable for stable kernels since
then.

Cc: stable@vger.kernel.org
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

parent 6c0544e2

drivers/md/raid5.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -606,6 +606,12 @@ static void ops_run_io(struct stripe_head sh, struct stripe_head_state s)
		* a chance*/
		md_check_recovery(conf->mddev);
		}
		/*
		* Because md_wait_for_blocked_rdev
		* will dec nr_pending, we must
		* increment it first.
		*/
		atomic_inc(&rdev->nr_pending);
		md_wait_for_blocked_rdev(rdev, conf->mddev);
		} else {
		/* Acknowledged bad block - skip the write */