3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: NeilBrown <ne...@suse.de>

commit b50c259e25d9260b9108dc0c2964c26e5ecbe1c1 upstream.

If we discover a bad block when reading we split the request and
potentially read some of it from a different device.

The code path of this has two bugs in RAID10.
1/ we get a spin_lock with _irq, but unlock without _irq!!
2/ The calculation of 'sectors_handled' is wrong, as can be clearly
   seen by comparison with raid1.c

This leads to at least 2 warnings and a probable crash is a RAID10
ever had known bad blocks.

Fixes: 856e08e23762dfb92ffc68fd0a8d228f9e152160
Reported-by: Damian Nowak <s...@nowaker.net>
URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181
Signed-off-by: NeilBrown <ne...@suse.de>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/md/raid10.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1117,7 +1117,7 @@ read_again:
                        /* Could not read all from this device, so we will
                         * need another r10_bio.
                         */
-                       sectors_handled = (r10_bio->sectors + max_sectors
+                       sectors_handled = (r10_bio->sector + max_sectors
                                           - bio->bi_sector);
                        r10_bio->sectors = max_sectors;
                        spin_lock_irq(&conf->device_lock);
@@ -1125,7 +1125,7 @@ read_again:
                                bio->bi_phys_segments = 2;
                        else
                                bio->bi_phys_segments++;
-                       spin_unlock(&conf->device_lock);
+                       spin_unlock_irq(&conf->device_lock);
                        /* Cannot call generic_make_request directly
                         * as that will be queued in __generic_make_request
                         * and subsequent mempool_alloc might block


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to