From: Greg Kroah-Hartman Date: Mon, 27 Jan 2014 20:06:46 +0000 (-0800) Subject: 3.10-stable patches X-Git-Tag: v3.13.1~4 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c9941698068210b9cf8a230cac6ec543560a1e86;p=thirdparty%2Fkernel%2Fstable-queue.git 3.10-stable patches added patches: md-raid5-fix-long-standing-problem-with-bitmap-handling-on-write-failure.patch --- diff --git a/queue-3.10/md-raid5-fix-long-standing-problem-with-bitmap-handling-on-write-failure.patch b/queue-3.10/md-raid5-fix-long-standing-problem-with-bitmap-handling-on-write-failure.patch new file mode 100644 index 00000000000..6bf33941a59 --- /dev/null +++ b/queue-3.10/md-raid5-fix-long-standing-problem-with-bitmap-handling-on-write-failure.patch @@ -0,0 +1,46 @@ +From 9f97e4b128d2ea90a5f5063ea0ee3b0911f4c669 Mon Sep 17 00:00:00 2001 +From: NeilBrown +Date: Thu, 16 Jan 2014 09:35:38 +1100 +Subject: md/raid5: fix long-standing problem with bitmap handling on write failure. + +From: NeilBrown + +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 +Signed-off-by: NeilBrown +Signed-off-by: Greg Kroah-Hartman + +--- + drivers/md/raid5.c | 1 + + 1 file changed, 1 insertion(+) + +--- a/drivers/md/raid5.c ++++ b/drivers/md/raid5.c +@@ -1893,6 +1893,7 @@ static void raid5_end_write_request(stru + 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)) diff --git a/queue-3.10/series b/queue-3.10/series index ac4d3c020f2..553908a40fd 100644 --- a/queue-3.10/series +++ b/queue-3.10/series @@ -1 +1,2 @@ kvm-x86-fix-apic_base-enable-check.patch +md-raid5-fix-long-standing-problem-with-bitmap-handling-on-write-failure.patch