From: NeilBrown Date: Thu, 19 Jul 2012 05:59:18 +0000 (+1000) Subject: md/raid1: close some possible races on write errors during resync X-Git-Tag: firefly_0821_release~3680^2~2277^2~19 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=58e94ae18478c08229626daece2fc108a4a23261;p=firefly-linux-kernel-4.4.55.git md/raid1: close some possible races on write errors during resync commit 4367af556133723d0f443e14ca8170d9447317cb md/raid1: clear bad-block record when write succeeds. Added a 'reschedule_retry' call possibility at the end of end_sync_write, but didn't add matching code at the end of sync_request_write. So if the writes complete very quickly, or scheduling makes it seem that way, then we can miss rescheduling the request and the resync could hang. Also commit 73d5c38a9536142e062c35997b044e89166e063b md: avoid races when stopping resync. Fix a race condition in this same code in end_sync_write but didn't make the change in sync_request_write. This patch updates sync_request_write to fix both of those. Patch is suitable for 3.1 and later kernels. Reported-by: Alexander Lyakas Original-version-by: Alexander Lyakas Cc: stable@vger.kernel.org Signed-off-by: NeilBrown --- diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 240ff3125040..cacd008d6864 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1818,8 +1818,14 @@ static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio) if (atomic_dec_and_test(&r1_bio->remaining)) { /* if we're here, all write(s) have completed, so clean up */ - md_done_sync(mddev, r1_bio->sectors, 1); - put_buf(r1_bio); + int s = r1_bio->sectors; + if (test_bit(R1BIO_MadeGood, &r1_bio->state) || + test_bit(R1BIO_WriteError, &r1_bio->state)) + reschedule_retry(r1_bio); + else { + put_buf(r1_bio); + md_done_sync(mddev, s, 1); + } } }