A fix for a writeback deadlock caused by a GFP_KERNEL allocation on the

reclaim path, tagged for stable.
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Merge tag 'ceph-for-4.11-rc4' of git://github.com/ceph/ceph-client

Pull ceph fix from Ilya Dryomov:
 "A fix for a writeback deadlock caused by a GFP_KERNEL allocation on
  the reclaim path, tagged for stable"

* tag 'ceph-for-4.11-rc4' of git://github.com/ceph/ceph-client:
  libceph: force GFP_NOIO for socket allocations
This commit is contained in:
Linus Torvalds 2017-03-24 14:35:39 -07:00
commit 59d9cb91d0

View File

@ -7,6 +7,7 @@
#include <linux/kthread.h>
#include <linux/net.h>
#include <linux/nsproxy.h>
#include <linux/sched/mm.h>
#include <linux/slab.h>
#include <linux/socket.h>
#include <linux/string.h>
@ -469,11 +470,16 @@ static int ceph_tcp_connect(struct ceph_connection *con)
{
struct sockaddr_storage *paddr = &con->peer_addr.in_addr;
struct socket *sock;
unsigned int noio_flag;
int ret;
BUG_ON(con->sock);
/* sock_create_kern() allocates with GFP_KERNEL */
noio_flag = memalloc_noio_save();
ret = sock_create_kern(read_pnet(&con->msgr->net), paddr->ss_family,
SOCK_STREAM, IPPROTO_TCP, &sock);
memalloc_noio_restore(noio_flag);
if (ret)
return ret;
sock->sk->sk_allocation = GFP_NOFS;