Commit 5020ad7d authored Apr 02, 2012 by NeilBrown

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



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 <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

parent c6d2e084

drivers/md/raid1.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1738,7 +1738,7 @@ static int process_checks(struct r1bio *r1_bio)
		s = sbio->bi_io_vec[j].bv_page;
		if (memcmp(page_address(p),
		page_address(s),
		PAGE_SIZE))
		sbio->bi_io_vec[j].bv_len))
		break;
		}
		} else

drivers/md/raid10.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1821,7 +1821,7 @@ static void sync_request_write(struct mddev mddev, struct r10bio r10_bio)
		for (j = 0; j < vcnt; j++)
		if (memcmp(page_address(fbio->bi_io_vec[j].bv_page),
		page_address(tbio->bi_io_vec[j].bv_page),
		PAGE_SIZE))
		fbio->bi_io_vec[j].bv_len))
		break;
		if (j == vcnt)
		continue;

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