Commit dbe82eb1 authored by Seth Jennings's avatar Seth Jennings Committed by Greg Kroah-Hartman
Browse files

staging: zcache: fix possible sleep under lock 



zcache_new_pool() calls kmalloc() with GFP_KERNEL which has
__GFP_WAIT set.  However, zcache_new_pool() gets called on
a stack that holds the swap_lock spinlock, leading to a
possible sleep-with-lock situation. The lock is obtained
in enable_swap_info().

The patch replaces GFP_KERNEL with GFP_ATOMIC.

v2: replace with GFP_ATOMIC, not GFP_IOFS

Signed-off-by: default avatarSeth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: default avatarDan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 58af5800

drivers/staging/zcache/zcache-main.c

+1 −1
Original line number Diff line number Diff line
@@ -1668,7 +1668,7 @@ static int zcache_new_pool(uint16_t cli_id, uint32_t flags) 
	if (cli == NULL)

		goto out;

	atomic_inc(&cli->refcount);

	pool = kmalloc(sizeof(struct tmem_pool), GFP_KERNEL);

	pool = kmalloc(sizeof(struct tmem_pool), GFP_ATOMIC);

	if (pool == NULL) {

		pr_info("zcache: pool creation failed: out of memory\n");

		goto out;