[KVM PATCH v3 1/3] kvm: fix potential coalesced_mmio leak on shutdown

[Gregory Haskins <ghaskins@novell.com>]

It would appear that we are invoking kfree() on the wrong pointer in the
destructor for the coalesced_mmio device.  This could result in a potential
leak during shutdown.  This works today because the kvm_io_device is
the first element of the private structure, but this could change in
the future, so lets clean this up.

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
---

 virt/kvm/coalesced_mmio.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index 5ae620d..03ea280 100644
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -80,7 +80,10 @@ static void coalesced_mmio_write(struct kvm_io_device *this,
 
 static void coalesced_mmio_destructor(struct kvm_io_device *this)
 {
-	kfree(this);
+	struct kvm_coalesced_mmio_dev *dev =
+		(struct kvm_coalesced_mmio_dev *)this->private;
+
+	kfree(dev);
 }
 
 int kvm_coalesced_mmio_init(struct kvm *kvm)