Hi On Thu, Jun 8, 2023 at 6:26 AM Jiqian Chen wrote: > After suspending and resuming guest VM, you will get > a black screen, and the display can't come back. > > This is because when guest did suspending, it called > into qemu to call virtio_gpu_gl_reset. In function > virtio_gpu_gl_reset, it destroyed resources and reset > renderer, which were used for display. As a result, > guest's screen can't come back to the time when it was > suspended and only showed black. > > So, this patch adds a new ctrl message > VIRTIO_GPU_CMD_STATUS_FREEZING to get notification from > guest. If guest is during suspending, it sets freezing > status of virtgpu to true, this will prevent destroying > resources and resetting renderer when guest calls into > virtio_gpu_gl_reset. If guest is during resuming, it sets > freezing to false, and then virtio_gpu_gl_reset will keep > its origin actions and has no other impaction. > > Signed-off-by: Jiqian Chen > --- > hw/display/virtio-gpu-gl.c | 9 ++++++- > hw/display/virtio-gpu-virgl.c | 3 +++ > hw/display/virtio-gpu.c | 26 +++++++++++++++++++-- > include/hw/virtio/virtio-gpu.h | 3 +++ > include/standard-headers/linux/virtio_gpu.h | 9 +++++++ > 5 files changed, 47 insertions(+), 3 deletions(-) > > diff --git a/hw/display/virtio-gpu-gl.c b/hw/display/virtio-gpu-gl.c > index e06be60dfb..e11ad233eb 100644 > --- a/hw/display/virtio-gpu-gl.c > +++ b/hw/display/virtio-gpu-gl.c > @@ -100,7 +100,14 @@ static void virtio_gpu_gl_reset(VirtIODevice *vdev) > */ > if (gl->renderer_inited && !gl->renderer_reset) { > virtio_gpu_virgl_reset_scanout(g); > - gl->renderer_reset = true; > + /* > + * If guest is suspending, we shouldn't reset renderer, > + * otherwise, the display can't come back to the time when > + * it was suspended after guest resumed. > + */ > + if (!g->freezing) { > + gl->renderer_reset = true; > + } > } > } > > diff --git a/hw/display/virtio-gpu-virgl.c b/hw/display/virtio-gpu-virgl.c > index 73cb92c8d5..183ec92d53 100644 > --- a/hw/display/virtio-gpu-virgl.c > +++ b/hw/display/virtio-gpu-virgl.c > @@ -464,6 +464,9 @@ void virtio_gpu_virgl_process_cmd(VirtIOGPU *g, > case VIRTIO_GPU_CMD_GET_EDID: > virtio_gpu_get_edid(g, cmd); > break; > + case VIRTIO_GPU_CMD_STATUS_FREEZING: > + virtio_gpu_cmd_status_freezing(g, cmd); > + break; > default: > cmd->error = VIRTIO_GPU_RESP_ERR_UNSPEC; > break; > diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c > index 5e15c79b94..8f235d7848 100644 > --- a/hw/display/virtio-gpu.c > +++ b/hw/display/virtio-gpu.c > @@ -373,6 +373,16 @@ static void virtio_gpu_resource_create_blob(VirtIOGPU > *g, > QTAILQ_INSERT_HEAD(&g->reslist, res, next); > } > > +void virtio_gpu_cmd_status_freezing(VirtIOGPU *g, > + struct virtio_gpu_ctrl_command *cmd) > +{ > + struct virtio_gpu_status_freezing sf; > + > + VIRTIO_GPU_FILL_CMD(sf); > + virtio_gpu_bswap_32(&sf, sizeof(sf)); > + g->freezing = sf.freezing; > +} > + > static void virtio_gpu_disable_scanout(VirtIOGPU *g, int scanout_id) > { > struct virtio_gpu_scanout *scanout = > &g->parent_obj.scanout[scanout_id]; > @@ -986,6 +996,9 @@ void virtio_gpu_simple_process_cmd(VirtIOGPU *g, > case VIRTIO_GPU_CMD_RESOURCE_DETACH_BACKING: > virtio_gpu_resource_detach_backing(g, cmd); > break; > + case VIRTIO_GPU_CMD_STATUS_FREEZING: > + virtio_gpu_cmd_status_freezing(g, cmd); > + break; > default: > cmd->error = VIRTIO_GPU_RESP_ERR_UNSPEC; > break; > @@ -1344,6 +1357,8 @@ void virtio_gpu_device_realize(DeviceState *qdev, > Error **errp) > QTAILQ_INIT(&g->reslist); > QTAILQ_INIT(&g->cmdq); > QTAILQ_INIT(&g->fenceq); > + > + g->freezing = false; > } > > void virtio_gpu_reset(VirtIODevice *vdev) > @@ -1352,8 +1367,15 @@ void virtio_gpu_reset(VirtIODevice *vdev) > struct virtio_gpu_simple_resource *res, *tmp; > struct virtio_gpu_ctrl_command *cmd; > > - QTAILQ_FOREACH_SAFE(res, &g->reslist, next, tmp) { > - virtio_gpu_resource_destroy(g, res); > + /* > + * If guest is suspending, we shouldn't destroy resources, > + * otherwise, the display can't come back to the time when > + * it was suspended after guest resumed. > + */ > + if (!g->freezing) { > + QTAILQ_FOREACH_SAFE(res, &g->reslist, next, tmp) { > + virtio_gpu_resource_destroy(g, res); > + } > } > > while (!QTAILQ_EMPTY(&g->cmdq)) { > diff --git a/include/hw/virtio/virtio-gpu.h > b/include/hw/virtio/virtio-gpu.h > index 2e28507efe..c21c2990fb 100644 > --- a/include/hw/virtio/virtio-gpu.h > +++ b/include/hw/virtio/virtio-gpu.h > @@ -173,6 +173,7 @@ struct VirtIOGPU { > > uint64_t hostmem; > > + bool freezing; > bool processing_cmdq; > QEMUTimer *fence_poll; > QEMUTimer *print_stats; > @@ -284,5 +285,7 @@ void virtio_gpu_virgl_reset_scanout(VirtIOGPU *g); > void virtio_gpu_virgl_reset(VirtIOGPU *g); > int virtio_gpu_virgl_init(VirtIOGPU *g); > int virtio_gpu_virgl_get_num_capsets(VirtIOGPU *g); > +void virtio_gpu_cmd_status_freezing(VirtIOGPU *g, > + struct virtio_gpu_ctrl_command *cmd); > > #endif > diff --git a/include/standard-headers/linux/virtio_gpu.h > b/include/standard-headers/linux/virtio_gpu.h > index 2da48d3d4c..aefffbd751 100644 > --- a/include/standard-headers/linux/virtio_gpu.h > +++ b/include/standard-headers/linux/virtio_gpu.h > @@ -116,6 +116,9 @@ enum virtio_gpu_ctrl_type { > VIRTIO_GPU_RESP_ERR_INVALID_RESOURCE_ID, > VIRTIO_GPU_RESP_ERR_INVALID_CONTEXT_ID, > VIRTIO_GPU_RESP_ERR_INVALID_PARAMETER, > + > + /* status */ > + VIRTIO_GPU_CMD_STATUS_FREEZING = 0x1300, > }; > Adding a new command requires new feature flag (and maybe it should be in the <0x1000 range instead) But I am not sure we need a new message at the virtio-gpu level. Gerd, wdyt? Maybe it's not a good place to reset all GPU resources during QEMU reset() after all, if it's called during s3 and there is no mechanism to restore it. Damien? thanks ... > enum virtio_gpu_shm_id { > @@ -453,4 +456,10 @@ struct virtio_gpu_resource_unmap_blob { > uint32_t padding; > }; > > +/* VIRTIO_GPU_CMD_STATUS_FREEZING */ > +struct virtio_gpu_status_freezing { > + struct virtio_gpu_ctrl_hdr hdr; > + __u32 freezing; > +}; > + > #endif > -- > 2.34.1 > > > -- Marc-André Lureau