The loop that frees all the pages can take unbounded amount of time, so add cond_resched() to it. Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> --- drivers/block/brd.c | 2 ++ 1 file changed, 2 insertions(+) Index: linux-4.19.41/drivers/block/brd.c =================================================================== --- linux-4.19.41.orig/drivers/block/brd.c 2019-01-22 12:26:42.000000000 +0100 +++ linux-4.19.41/drivers/block/brd.c 2019-05-09 17:09:11.000000000 +0200 @@ -157,6 +157,8 @@ static void brd_free_pages(struct brd_de pos++; + cond_resched(); + /* * This assumes radix_tree_gang_lookup always returns as * many pages as possible. If the radix-tree code changes,
