kernel/linux.git/drivers/md/raid1.c, branch v3.4.34

md/raid1: Fix assembling of arrays containing Replacements.

2012-11-05T08:50:41+00:00

commit 02b898f2f04e418094f0093a3ad0b415bcdbe8eb upstream. setup_conf in raid1.c uses conf->raid_disks before assigning a value. It is used when including 'Replacement' devices. The consequence is that assembling an array which contains a replacement will misbehave and either not include the replacement, or not include the device being replaced. Though this doesn't lead directly to data corruption, it could lead to reduced data safety. So use mddev->raid_disks, which is initialised, instead. Bug was introduced by commit c19d57980b38a5bb613a898937a1cf85f422fb9b md/raid1: recognise replacements when assembling arrays. in 3.3, so fix is suitable for 3.3.y thru 3.6.y. Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md/raid1: don't abort a resync on the first badblock.

2012-08-15T15:10:08+00:00

commit b7219ccb33aa0df9949a60c68b5e9f712615e56f upstream. If a resync of a RAID1 array with 2 devices finds a known bad block one device it will neither read from, or write to, that device for this block offset. So there will be one read_target (The other device) and zero write targets. This condition causes md/raid1 to abort the resync assuming that it has finished - without known bad blocks this would be true. When there are no write targets because of the presence of bad blocks we should only skip over the area covered by the bad block. RAID10 already gets this right, raid1 doesn't. Or didn't. As this can cause a 'sync' to abort early and appear to have succeeded it could lead to some data corruption, so it suitable for -stable. Reported-by: Alexander Lyakas Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

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

2012-07-29T15:04:17+00:00

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 Original-version-by: Alexander Lyakas Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md/raid1: fix use-after-free bug in RAID1 data-check code.

2012-07-19T15:58:55+00:00

commit 2d4f4f3384d4ef4f7c571448e803a1ce721113d5 upstream. This bug has been present ever since data-check was introduce in 2.6.16. However it would only fire if a data-check were done on a degraded array, which was only possible if the array has 3 or more devices. This is certainly possible, but is quite uncommon. Since hot-replace was added in 3.3 it can happen more often as the same condition can arise if not all possible replacements are present. The problem is that as soon as we submit the last read request, the 'r1_bio' structure could be freed at any time, so we really should stop looking at it. If the last device is being read from we will stop looking at it. However if the last device is not due to be read from, we will still check the bio pointer in the r1_bio, but the r1_bio might already be free. So use the read_targets counter to make sure we stop looking for bios to submit as soon as we have submitted them all. This fix is suitable for any -stable kernel since 2.6.16. Reported-by: Arnold Schulz Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: raid1/raid10: fix problem with merge_bvec_fn

2012-06-09T15:36:18+00:00

commit aba336bd1d46d6b0404b06f6915ed76150739057 upstream. The new merge_bvec_fn which calls the corresponding function in subsidiary devices requires that mddev->merge_check_needed be set if any child has a merge_bvec_fn. However were were only setting that when a device was hot-added, not when a device was present from the start. This bug was introduced in 3.4 so patch is suitable for 3.4.y kernels. However that are conflicts in raid10.c so a separate patch will be needed for 3.4.y. Reported-by: Sebastian Riemer Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md/raid1,raid10: Fix calculation of 'vcnt' when processing error recovery.

2012-04-12T06:04:47+00:00

If r1bio->sectors % 8 != 0,then the memcmp and a later memcpy will omit the last bio_vec. This is suitable for any stable kernel since 3.1 when bad-block management was introduced. Cc: stable@vger.kernel.org Signed-off-by: majianpeng Signed-off-by: NeilBrown

md/raid1,raid10: don't compare excess byte during consistency check.

2012-04-03T05:39:23+00:00

When comparing two pages read from different legs of a mirror, only compare the bytes that were read, not the whole page. In most cases we read a whole page, but in some cases with bad blocks or odd sizes devices we might read fewer than that. This bug has been present "forever" but at worst it might cause a report of two many mismatches and generate a little bit extra resync IO, so there is no need to back-port to -stable kernels. Reported-by: majianpeng Signed-off-by: NeilBrown

md/raid1:Remove unnecessary rcu_dereference(conf->mirrors[i].rdev).

2012-04-03T05:37:33+00:00

Because rde->nr_pending > 0,so can not remove this disk. And in any case, we aren't holding rcu_read_lock() Signed-off-by: majianpeng Signed-off-by: NeilBrown

md/raid1: If md_integrity_register() failed,run() must free the mem

2012-04-01T23:48:38+00:00

Signed-off-by: majianpeng Signed-off-by: NeilBrown

md/raid1: handle merge_bvec_fn in member devices.

2012-03-19T01:46:39+00:00

Currently we don't honour merge_bvec_fn in member devices so if there is one, we force all requests to be single-page at most. This is not ideal. So create a raid1 merge_bvec_fn to check that function in children as well. This introduces a small problem. There is no locking around calls the ->merge_bvec_fn and subsequent calls to ->make_request. So a device added between these could end up getting a request which violates its merge_bvec_fn. Currently the best we can do is synchronize_sched(). This will work providing no preemption happens. If there is is preemption, we just have to hope that new devices are largely consistent with old devices. Signed-off-by: NeilBrown