From: NeilBrown Date: Tue, 3 Jul 2012 00:37:30 +0000 (+1000) Subject: md/raid10: Don't try to recovery unmatched (and unused) chunks. X-Git-Tag: firefly_0821_release~7541^2~961 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=cc675040202e8f4e825a91997319b4b0bf9e9960;p=firefly-linux-kernel-4.4.55.git md/raid10: Don't try to recovery unmatched (and unused) chunks. commit fc448a18ae6219af9a73257b1fbcd009efab4a81 upstream. If a RAID10 has an odd number of chunks - as might happen when there are an odd number of devices - the last chunk has no pair and so is not mirrored. We don't store data there, but when recovering the last device in an array we retry to recover that last chunk from a non-existent location. This results in an error, and the recovery aborts. When we get to that last chunk we should just stop - there is nothing more to do anyway. This bug has been present since the introduction of RAID10, so the patch is appropriate for any -stable kernel. Reported-by: Christian Balzer Tested-by: Christian Balzer Signed-off-by: NeilBrown [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 0d6c42f70a35..b65a7c50eb63 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1858,6 +1858,12 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, /* want to reconstruct this device */ rb2 = r10_bio; sect = raid10_find_virt(conf, sector_nr, i); + if (sect >= mddev->resync_max_sectors) { + /* last stripe is not complete - don't + * try to recover this sector. + */ + continue; + } /* Unless we are doing a full sync, we only need * to recover the block if it is set in the bitmap */