[V6,1/6] kvm: don't try to register to KVM_FAST_MMIO_BUS for non mmio eventfd
diff mbox series

Message ID 1442299319-5253-2-git-send-email-jasowang@redhat.com
State New, archived
Headers show
Series
  • Fast mmio eventfd fixes
Related show

Commit Message

Jason Wang Sept. 15, 2015, 6:41 a.m. UTC
We only want zero length mmio eventfd to be registered on
KVM_FAST_MMIO_BUS. So check this explicitly when arg->len is zero to
make sure this.

Cc: stable@vger.kernel.org
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 virt/kvm/eventfd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Cornelia Huck Sept. 15, 2015, 7:05 a.m. UTC | #1
On Tue, 15 Sep 2015 14:41:54 +0800
Jason Wang <jasowang@redhat.com> wrote:

> We only want zero length mmio eventfd to be registered on
> KVM_FAST_MMIO_BUS. So check this explicitly when arg->len is zero to
> make sure this.
> 
> Cc: stable@vger.kernel.org
> Cc: Gleb Natapov <gleb@kernel.org>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  virt/kvm/eventfd.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>

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Patch
diff mbox series

diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 9ff4193..e404806 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -846,7 +846,7 @@  kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
 	/* When length is ignored, MMIO is also put on a separate bus, for
 	 * faster lookups.
 	 */
-	if (!args->len && !(args->flags & KVM_IOEVENTFD_FLAG_PIO)) {
+	if (!args->len && bus_idx == KVM_MMIO_BUS) {
 		ret = kvm_io_bus_register_dev(kvm, KVM_FAST_MMIO_BUS,
 					      p->addr, 0, &p->dev);
 		if (ret < 0)
@@ -901,7 +901,7 @@  kvm_deassign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
 			continue;
 
 		kvm_io_bus_unregister_dev(kvm, bus_idx, &p->dev);
-		if (!p->length) {
+		if (!p->length && p->bus_idx == KVM_MMIO_BUS) {
 			kvm_io_bus_unregister_dev(kvm, KVM_FAST_MMIO_BUS,
 						  &p->dev);
 		}