diff options
| author | NeilBrown <neilb@suse.com> | 2018-04-26 06:46:29 +0200 |
|---|---|---|
| committer | Shaohua Li <shli@fb.com> | 2018-05-01 18:47:50 +0200 |
| commit | 011abdc9df559ec75779bb7c53a744c69b2a94c6 (patch) | |
| tree | 2907219095e95dd67455f209ee5d96a5b0d8068e /drivers/md | |
| parent | raid10: check bio in r10buf_pool_free to void NULL pointer dereference (diff) | |
| download | linux-011abdc9df559ec75779bb7c53a744c69b2a94c6.tar.xz linux-011abdc9df559ec75779bb7c53a744c69b2a94c6.zip | |
md: fix two problems with setting the "re-add" device state.
If "re-add" is written to the "state" file for a device
which is faulty, this has an effect similar to removing
and re-adding the device. It should take up the
same slot in the array that it previously had, and
an accelerated (e.g. bitmap-based) rebuild should happen.
The slot that "it previously had" is determined by
rdev->saved_raid_disk.
However this is not set when a device fails (only when a device
is added), and it is cleared when resync completes.
This means that "re-add" will normally work once, but may not work a
second time.
This patch includes two fixes.
1/ when a device fails, record the ->raid_disk value in
->saved_raid_disk before clearing ->raid_disk
2/ when "re-add" is written to a device for which
->saved_raid_disk is not set, fail.
I think this is suitable for stable as it can
cause re-adding a device to be forced to do a full
resync which takes a lot longer and so puts data at
more risk.
Cc: <stable@vger.kernel.org> (v4.1)
Fixes: 97f6cd39da22 ("md-cluster: re-add capabilities")
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/md.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index c208c01f63a5..bac480d75d1d 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2853,7 +2853,8 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len) err = 0; } } else if (cmd_match(buf, "re-add")) { - if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1)) { + if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) && + rdev->saved_raid_disk >= 0) { /* clear_bit is performed _after_ all the devices * have their local Faulty bit cleared. If any writes * happen in the meantime in the local node, they @@ -8641,6 +8642,7 @@ static int remove_and_add_spares(struct mddev *mddev, if (mddev->pers->hot_remove_disk( mddev, rdev) == 0) { sysfs_unlink_rdev(mddev, rdev); + rdev->saved_raid_disk = rdev->raid_disk; rdev->raid_disk = -1; removed++; } |