diff options
Diffstat (limited to 'hw/virtio.c')
-rw-r--r-- | hw/virtio.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/hw/virtio.c b/hw/virtio.c index 337ff27ba9..1f92171f68 100644 --- a/hw/virtio.c +++ b/hw/virtio.c @@ -23,8 +23,11 @@ /* QEMU doesn't strictly need write barriers since everything runs in * lock-step. We'll leave the calls to wmb() in though to make it obvious for * KVM or if kqemu gets SMP support. + * In any case, we must prevent the compiler from reordering the code. + * TODO: we likely need some rmb()/mb() as well. */ -#define wmb() do { } while (0) + +#define wmb() __asm__ __volatile__("": : :"memory") typedef struct VRingDesc { |