| From | Greg Kroah-Hartman <> | Subject | [ 131/187] md/raid5: In ops_run_io, inc nr_pending before calling md_wait_for_blocked_rdev | Date | Thu, 12 Jul 2012 15:34:47 -0700 |
| |
From: Greg KH <gregkh@linuxfoundation.org>
3.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: majianpeng <majianpeng@gmail.com>
commit 1850753d2e6d9ca7856581ca5d3cf09521e6a5d7 upstream.
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 73e92e51b7969ef5477d 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.
Signed-off-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/md/raid5.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -583,6 +583,12 @@ static void ops_run_io(struct stripe_hea * 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 */
|