vhost-user-gpu: handle display-info in a callback

Fixes a deadlock where the backend calls QEMU, while QEMU also calls the
backend simultaneously, both ends waiting for each other.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210204105232.834642-5-marcandre.lureau@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Marc-André Lureau 2021-02-04 14:52:16 +04:00 committed by Gerd Hoffmann
parent 72e631c6ac
commit bd690feb15

View File

@ -261,10 +261,33 @@ vg_ctrl_response_nodata(VuGpu *g,
vg_ctrl_response(g, cmd, &resp, sizeof(resp)); vg_ctrl_response(g, cmd, &resp, sizeof(resp));
} }
static gboolean
get_display_info_cb(gint fd, GIOCondition condition, gpointer user_data)
{
struct virtio_gpu_resp_display_info dpy_info = { {} };
VuGpu *vg = user_data;
struct virtio_gpu_ctrl_command *cmd = QTAILQ_LAST(&vg->fenceq);
g_debug("disp info cb");
assert(cmd->cmd_hdr.type == VIRTIO_GPU_CMD_GET_DISPLAY_INFO);
if (!vg_recv_msg(vg, VHOST_USER_GPU_GET_DISPLAY_INFO,
sizeof(dpy_info), &dpy_info)) {
return G_SOURCE_CONTINUE;
}
QTAILQ_REMOVE(&vg->fenceq, cmd, next);
vg_ctrl_response(vg, cmd, &dpy_info.hdr, sizeof(dpy_info));
vg->wait_in = 0;
vg_handle_ctrl(&vg->dev.parent, 0);
return G_SOURCE_REMOVE;
}
void void
vg_get_display_info(VuGpu *vg, struct virtio_gpu_ctrl_command *cmd) vg_get_display_info(VuGpu *vg, struct virtio_gpu_ctrl_command *cmd)
{ {
struct virtio_gpu_resp_display_info dpy_info = { {} };
VhostUserGpuMsg msg = { VhostUserGpuMsg msg = {
.request = VHOST_USER_GPU_GET_DISPLAY_INFO, .request = VHOST_USER_GPU_GET_DISPLAY_INFO,
.size = 0, .size = 0,
@ -273,11 +296,9 @@ vg_get_display_info(VuGpu *vg, struct virtio_gpu_ctrl_command *cmd)
assert(vg->wait_in == 0); assert(vg->wait_in == 0);
vg_send_msg(vg, &msg, -1); vg_send_msg(vg, &msg, -1);
if (!vg_recv_msg(vg, msg.request, sizeof(dpy_info), &dpy_info)) { vg->wait_in = g_unix_fd_add(vg->sock_fd, G_IO_IN | G_IO_HUP,
return; get_display_info_cb, vg);
} cmd->state = VG_CMD_STATE_PENDING;
vg_ctrl_response(vg, cmd, &dpy_info.hdr, sizeof(dpy_info));
} }
static void static void