From 8710ae43b6dd5dc0935dea03102f937604cb7790 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 6 Jan 2014 13:19:42 +1100 Subject: [PATCH] md/raid5: Fix possible confusion when multiple write errors occur. commit 3243fd054b61a542fefc5c01a991b37c071ac7ed md: raid5 crash during degradation Fixed a crash in an overly simplistic way which could leave R5_WriteError or R5_MadeGood set in the stripe cache for devices for which it is no longer relevant. When those devices are removed and spares added the flags are still set and can cause incorrect behaviour. commit 7802ce65fd818b1ebb87c5b8ebc8fdd3767e005c md/raid5: preferentially read from replacement device if possible. Fixed the same bug if a more effective way, so we can now revert the original commit. Reported-and-tested-by: Alexander Lyakas Cc: stable@vger.kernel.org (3.2+ - 3.2 will need a different fix though) Fixes: 3243fd054b61a542fefc5c01a991b37c071ac7ed Signed-off-by: NeilBrown --- drivers/md/raid5.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index cc055da02e2a3..9168173deaf30 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3608,7 +3608,7 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s) */ set_bit(R5_Insync, &dev->flags); - if (rdev && test_bit(R5_WriteError, &dev->flags)) { + if (test_bit(R5_WriteError, &dev->flags)) { /* This flag does not apply to '.replacement' * only to .rdev, so make sure to check that*/ struct md_rdev *rdev2 = rcu_dereference( @@ -3621,7 +3621,7 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s) } else clear_bit(R5_WriteError, &dev->flags); } - if (rdev && test_bit(R5_MadeGood, &dev->flags)) { + if (test_bit(R5_MadeGood, &dev->flags)) { /* This flag does not apply to '.replacement' * only to .rdev, so make sure to check that*/ struct md_rdev *rdev2 = rcu_dereference( -- 2.39.5