diff options
| author | NeilBrown <neilb@suse.com> | 2016-06-02 06:19:52 (GMT) |
|---|---|---|
| committer | Shaohua Li <shli@fb.com> | 2016-06-13 18:54:14 (GMT) |
| commit | d44b0a928fa9925fb453d7acc42a48c79de2c6f7 (patch) | |
| tree | 24351c0d633aeec643c7f39ef6642096d4255dc3 /drivers/md/raid10.c | |
| parent | 83f1261f5e5516d7cf58a04b97e4e63e747a9157 (diff) | |
| download | linux-d44b0a928fa9925fb453d7acc42a48c79de2c6f7.tar.xz | |
md/raid10: add rcu protection in raid10_status.
mirrors[].rdev can become NULL at any point unless:
- a counted reference is held
- ->reconfig_mutex is held, or
- rcu_read_lock() is held
raid10_status holds none of these. So add rcu_read_lock()
protection.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Diffstat (limited to 'drivers/md/raid10.c')
| -rw-r--r-- | drivers/md/raid10.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 6044864..334a701 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1495,10 +1495,12 @@ static void raid10_status(struct seq_file *seq, struct mddev *mddev) } seq_printf(seq, " [%d/%d] [", conf->geo.raid_disks, conf->geo.raid_disks - mddev->degraded); - for (i = 0; i < conf->geo.raid_disks; i++) - seq_printf(seq, "%s", - conf->mirrors[i].rdev && - test_bit(In_sync, &conf->mirrors[i].rdev->flags) ? "U" : "_"); + rcu_read_lock(); + for (i = 0; i < conf->geo.raid_disks; i++) { + struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); + seq_printf(seq, "%s", rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_"); + } + rcu_read_unlock(); seq_printf(seq, "]"); } |