md: rcu_read_lock() walk of mddev->disks in md_do_sync()
Other walks of this list are either under rcu_read_lock() or the list
mutation lock (mddev_lock()). This protects against the improbable case of a
disk being removed from the array at the start of md_do_sync().
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 68a8a29..ea64a68 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6526,12 +6526,14 @@
/* recovery follows the physical size of devices */
max_sectors = mddev->dev_sectors;
j = MaxSector;
- list_for_each_entry(rdev, &mddev->disks, same_set)
+ rcu_read_lock();
+ list_for_each_entry_rcu(rdev, &mddev->disks, same_set)
if (rdev->raid_disk >= 0 &&
!test_bit(Faulty, &rdev->flags) &&
!test_bit(In_sync, &rdev->flags) &&
rdev->recovery_offset < j)
j = rdev->recovery_offset;
+ rcu_read_unlock();
}
printk(KERN_INFO "md: %s of RAID array %s\n", desc, mdname(mddev));
@@ -6701,12 +6703,14 @@
} else {
if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
mddev->curr_resync = MaxSector;
- list_for_each_entry(rdev, &mddev->disks, same_set)
+ rcu_read_lock();
+ list_for_each_entry_rcu(rdev, &mddev->disks, same_set)
if (rdev->raid_disk >= 0 &&
!test_bit(Faulty, &rdev->flags) &&
!test_bit(In_sync, &rdev->flags) &&
rdev->recovery_offset < mddev->curr_resync)
rdev->recovery_offset = mddev->curr_resync;
+ rcu_read_unlock();
}
}
set_bit(MD_CHANGE_DEVS, &mddev->flags);