md: fix a potential deadlock of raid5/raid10 reshape

[sfrench/cifs-2.6.git] / drivers / md / raid5.c

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 50d01144b80535e2e937c16021cdeeba632b201e..b5d2601483e34fa97fc8cfb7faeff6f014c0e035 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2196,15 +2196,16 @@ static int grow_one_stripe(struct r5conf *conf, gfp_t gfp)
 static int grow_stripes(struct r5conf *conf, int num)
 {
        struct kmem_cache *sc;
+       size_t namelen = sizeof(conf->cache_name[0]);
        int devs = max(conf->raid_disks, conf->previous_raid_disks);
 
        if (conf->mddev->gendisk)
-               sprintf(conf->cache_name[0],
+               snprintf(conf->cache_name[0], namelen,
                        "raid%d-%s", conf->level, mdname(conf->mddev));
        else
-               sprintf(conf->cache_name[0],
+               snprintf(conf->cache_name[0], namelen,
                        "raid%d-%p", conf->level, conf->mddev);
-       sprintf(conf->cache_name[1], "%s-alt", conf->cache_name[0]);
+       snprintf(conf->cache_name[1], namelen, "%.27s-alt", conf->cache_name[0]);
 
        conf->active_name = 0;
        sc = kmem_cache_create(conf->cache_name[conf->active_name],
@@ -6764,9 +6765,7 @@ static void free_conf(struct r5conf *conf)
 
        log_exit(conf);
 
-       if (conf->shrinker.nr_deferred)
-               unregister_shrinker(&conf->shrinker);
-
+       unregister_shrinker(&conf->shrinker);
        free_thread_groups(conf);
        shrink_stripes(conf);
        raid5_free_percpu(conf);
@@ -8001,13 +8000,7 @@ static void raid5_finish_reshape(struct mddev *mddev)
 
        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
 
-               if (mddev->delta_disks > 0) {
-                       md_set_array_sectors(mddev, raid5_size(mddev, 0, 0));
-                       if (mddev->queue) {
-                               set_capacity(mddev->gendisk, mddev->array_sectors);
-                               revalidate_disk(mddev->gendisk);
-                       }
-               } else {
+               if (mddev->delta_disks <= 0) {
                        int d;
                        spin_lock_irq(&conf->device_lock);
                        mddev->degraded = raid5_calc_degraded(conf);