Commit 0f94e87c authored Jan 08, 2008 by Dan Williams Committed by Linus Torvalds Jan 08, 2008

md: fix data corruption when a degraded raid5 array is reshaped



We currently do not wait for the block from the missing device to be
computed from parity before copying data to the new stripe layout.

The change in the raid6 code is not techincally needed as we don't delay
data block recovery in the same way for raid6 yet.  But making the change
now is safer long-term.

This bug exists in 2.6.23 and 2.6.24-rc

Cc: <stable@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 5b7741b3

drivers/md/raid5.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -2865,7 +2865,8 @@ static void handle_stripe5(struct stripe_head *sh)
		md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
		}

		if (s.expanding && s.locked == 0)
		if (s.expanding && s.locked == 0 &&
		!test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending))
		handle_stripe_expansion(conf, sh, NULL);

		if (sh->ops.count)
		@@ -3067,7 +3068,8 @@ static void handle_stripe6(struct stripe_head sh, struct page tmp_page)
		md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
		}

		if (s.expanding && s.locked == 0)
		if (s.expanding && s.locked == 0 &&
		!test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending))
		handle_stripe_expansion(conf, sh, &r6s);

		spin_unlock(&sh->lock);

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