From: Amit Shah <amit.shah@redhat.com>
Date: Thu, 22 Apr 2010 07:59:00 -0400
Subject: [virtio] fix GFP flags passed by virtio balloon driver
Message-id: <1271923140-13369-1-git-send-email-amit.shah@redhat.com>
Patchwork-id: 24292
O-Subject: [RHEL5.6 PATCH] virtio: Fix GFP flags passed from the virtio balloon
	driver
Bugzilla: 584683
RH-Acked-by: Michael S. Tsirkin <mst@redhat.com>

From: Balbir Singh <balbir@linux.vnet.ibm.com>

The virtio balloon driver can dig into the reservation pools
of the OS to satisfy a balloon request. This is not advisable
and other balloon drivers (drivers/xen/balloon.c) avoid this
as well. The patch also adds changes to avoid printing a warning
if allocation fails, since we retry after sometime anyway.

Bugzilla: 584683

Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: kvm <kvm@vger.kernel.org>
Cc: stable@kernel.org
Signed-off-by: Amit Shah <amit.shah@redhat.com>

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 3e16229..b5b5d26 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -100,7 +100,8 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num)
 	num = min(num, ARRAY_SIZE(vb->pfns));
 
 	for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) {
-		struct page *page = alloc_page(GFP_HIGHUSER | __GFP_NORETRY);
+		struct page *page = alloc_page(GFP_HIGHUSER | __GFP_NORETRY |
+					__GFP_NOMEMALLOC | __GFP_NOWARN);
 		if (!page) {
 			if (printk_ratelimit())
 				dev_printk(KERN_INFO, &vb->vdev->dev,