vq->avail is a 16bit value, so read and write it with readw()/writew() instead of readl()/writel().
To read/write a 16bit value with a 32bit accessor works fine on little-endian CPU but not on big endian CPU. Signed-off-by: Laurent Vivier <lviv...@redhat.com> --- tests/libqos/virtio.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tests/libqos/virtio.c b/tests/libqos/virtio.c index d8c2970..25d5b97 100644 --- a/tests/libqos/virtio.c +++ b/tests/libqos/virtio.c @@ -257,7 +257,7 @@ void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq, uint32_t free_head) { /* vq->avail->idx */ - uint16_t idx = readl(vq->avail + 2); + uint16_t idx = readw(vq->avail + 2); /* vq->used->flags */ uint16_t flags; /* vq->used->avail_event */ @@ -266,7 +266,7 @@ void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq, /* vq->avail->ring[idx % vq->size] */ writel(vq->avail + 4 + (2 * (idx % vq->size)), free_head); /* vq->avail->idx */ - writel(vq->avail + 2, idx + 1); + writew(vq->avail + 2, idx + 1); /* Must read after idx is updated */ flags = readw(vq->avail); -- 2.5.5