Commit 58e94ae1 authored Jul 19, 2012 by NeilBrown

md/raid1: close some possible races on write errors during resync



commit 4367af55
   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 73d5c38a
    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>
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>

parent a05b7ea0

drivers/md/raid1.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -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);
		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);
		}
		}
		}

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