From: Eugenio Pérez eperezma@redhat.com
[ Upstream commit 0e84f918fac8ae61dcb790534fad5e3555ca2930 ]
vdpasim_queue_ready calls vringh_init_iotlb, which resets split indexes. But it can be called after setting a ring base with vdpasim_set_vq_state.
Fix it by stashing them. They're still resetted in vdpasim_vq_reset.
This was discovered and tested live migrating the vdpa_sim_net device.
Fixes: 2c53d0f64c06 ("vdpasim: vDPA device simulator") Signed-off-by: Eugenio Pérez eperezma@redhat.com Message-Id: 20230118164359.1523760-2-eperezma@redhat.com Signed-off-by: Michael S. Tsirkin mst@redhat.com Acked-by: Jason Wang jasowang@redhat.com Tested-by: Lei Yang leiyang@redhat.com Stable-dep-of: b4cca6d48eb3 ("vdpa_sim: set last_used_idx as last_avail_idx in vdpasim_queue_ready") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/vdpa/vdpa_sim/vdpa_sim.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c index cb88891b44a8c..8839232a3fcbc 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -66,6 +66,7 @@ static void vdpasim_vq_notify(struct vringh *vring) static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) { struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; + uint16_t last_avail_idx = vq->vring.last_avail_idx;
vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, false, (struct vring_desc *)(uintptr_t)vq->desc_addr, @@ -74,6 +75,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx) (struct vring_used *) (uintptr_t)vq->device_addr);
+ vq->vring.last_avail_idx = last_avail_idx; vq->vring.notify = vdpasim_vq_notify; }