dm snapshot: fix lockup in dm_exception_table_exit
There was reported lockup when we exit a snapshot with many exceptions.
Fix this by adding "cond_resched" to the loop that frees the exceptions.
Reported-by: John Pittman <jpittman@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index bf7a574..0ace06d 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -684,8 +684,10 @@
for (i = 0; i < size; i++) {
slot = et->table + i;
- hlist_bl_for_each_entry_safe(ex, pos, n, slot, hash_list)
+ hlist_bl_for_each_entry_safe(ex, pos, n, slot, hash_list) {
kmem_cache_free(mem, ex);
+ cond_resched();
+ }
}
kvfree(et->table);