| From: NeilBrown <neilb@suse.de> |
| Date: Thu, 19 Jul 2012 15:59:18 +1000 |
| Subject: md/raid1: close some possible races on write errors during resync |
| |
| commit 58e94ae18478c08229626daece2fc108a4a23261 upstream. |
| |
| 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 <alex.bolshoy@gmail.com> |
| Original-version-by: Alexander Lyakas <alex.bolshoy@gmail.com> |
| Signed-off-by: NeilBrown <neilb@suse.de> |
| Signed-off-by: Ben Hutchings <ben@decadent.org.uk> |
| --- |
| drivers/md/raid1.c | 10 ++++++++-- |
| 1 file changed, 8 insertions(+), 2 deletions(-) |
| |
| diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c |
| index 240ff31..cacd008 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); |
| + } |
| } |
| } |
| |
