| Message ID | 1391596763-20741-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 4ee5324..eb0f9ea 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -1851,6 +1851,7 @@ static void raid5_end_write_request(struct bio *bi, int error) set_bit(R5_MadeGoodRepl, &sh->dev[i].flags); } else { if (!uptodate) { + set_bit(STRIPE_DEGRADED, &sh->state); set_bit(WriteErrorSeen, &rdev->flags); set_bit(R5_WriteError, &sh->dev[i].flags); if (!test_and_set_bit(WantReplacement, &rdev->flags))
This is a note to let you know that I have just added a patch titled md/raid5: fix long-standing problem with bitmap handling on write to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 402edbb8db5c99fd45dbe2945e14a7a75240e84f Mon Sep 17 00:00:00 2001 From: NeilBrown <neilb@suse.de> Date: Thu, 16 Jan 2014 09:35:38 +1100 Subject: md/raid5: fix long-standing problem with bitmap handling on write failure. commit 9f97e4b128d2ea90a5f5063ea0ee3b0911f4c669 upstream. Before a write starts we set a bit in the write-intent bitmap. When the write completes we clear that bit if the write was successful to all devices. However if the write wasn't fully successful we should not clear the bit. If the faulty drive is subsequently re-added, the fact that the bit is still set ensure that we will re-write the data that is missing. This logic is mediated by the STRIPE_DEGRADED flag - we only clear the bitmap bit when this flag is not set. Currently we correctly set the flag if a write starts when some devices are failed or missing. But we do *not* set the flag if some device failed during the write attempt. This is wrong and can result in clearing the bit inappropriately. So: set the flag when a write fails. This bug has been present since bitmaps were introduces, so the fix is suitable for any -stable kernel. Reported-by: Ethan Wilson <ethan.wilson@shiftmail.org> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/md/raid5.c | 1 + 1 file changed, 1 insertion(+) -- 1.8.3.2