From: David Hildenbrand <david@redhat.com>
Date: Wed, 20 May 2020 10:04:38 +0000 (+0200)
Subject: virtio-balloon: fix free page hinting check on unrealize
X-Git-Tag: qemu-xen-4.14.1^2~72
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=945d9273c8234dcc2f301059fe294df5e722b055;p=qemu-xen.git

virtio-balloon: fix free page hinting check on unrealize

Checking against guest features is wrong. We allocated data structures
based on host features. We can rely on "free_page_bh" as an indicator
whether to un-do stuff instead.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Fixes: c13c4153f76d ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Cc: qemu-stable@nongnu.org
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200520100439.19872-3-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 49b01711b8eb3796c6904c7f85d2431572cfe54f)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---

diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index ef499e1b3b..3e3b5ff0f8 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -818,7 +818,7 @@ static void virtio_balloon_device_unrealize(DeviceState *dev, Error **errp)
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
     VirtIOBalloon *s = VIRTIO_BALLOON(dev);
 
-    if (virtio_balloon_free_page_support(s)) {
+    if (s->free_page_bh) {
         qemu_bh_delete(s->free_page_bh);
         virtio_balloon_free_page_stop(s);
         precopy_remove_notifier(&s->free_page_report_notify);