Gerd, another thing with virtio-gpu. I can successfully do suspend/resume (echo disk > /sys/power/state) on my system. As soon as I have a virtio-gpu the system hangs on reboot/shutdown: e.g. crash> bt 1 PID: 1 TASK: 6bef0000 CPU: 4 COMMAND: "systemd" #0 [6beef4c0] __schedule at a55d60 #1 [6beef530] schedule at a563f2 #2 [6beef548] virtio_gpu_queue_ctrl_buffer_locked at 7ea708 #3 [6beef650] virtio_gpu_queue_ctrl_buffer at 7ea830 #4 [6beef680] virtio_gpu_primary_plane_update at 7ed5ee #5 [6beef710] drm_atomic_helper_commit_planes at 7a2b46 #6 [6beef760] vgdev_atomic_commit_tail at 7e9dbc #7 [6beef790] commit_tail at 7a7126 #8 [6beef7c0] drm_atomic_helper_commit at 7a73fe #9 [6beef800] restore_fbdev_mode_atomic at 7aa38a #10 [6beef8a0] drm_fb_helper_pan_display at 7ab7aa #11 [6beef8f0] fb_pan_display at 74a248 #12 [6beef928] bit_update_start at 7573c0 #13 [6beef958] fbcon_switch at 7542b4 #14 [6beefa50] redraw_screen at 77b2b8 #15 [6beefaa0] csi_J at 77b476 #16 [6beefad8] do_con_trol at 77ee12 #17 [6beefb40] do_con_write at 77f80c #18 [6beefc10] con_write at 78003c #19 [6beefc40] n_tty_write at 7662d4 #20 [6beefce0] tty_write at 761734 #21 [6beefd48] __vfs_write at 3483cc #22 [6beefe00] vfs_write at 3486e8 #23 [6beefe60] sys_write at 3489de #24 [6beefea8] system_call at a5b6a8 PSW: 0705100180000000 000003ff8111251c (user space) GPRS: 0000000000000000 000003ff00000002 000000000000000e 000003ff80deaef0 000000000000000a 0000000000000000 000000000000000f 00000000000003ef 0000000000000000 000000000000000e 000003ff80deaef0 000000000000000a 000003ff81228f58 000000000000000e 000003ff81112510 000003fffdefedf8 Turns out that the virtio-gpu console (via vnc) prints the image loading but then stops and show no login prompt. (but agetty is running on tty1) So I assume it already hangs after resume (and I am working on the serial sclp console). Does suspend resume works for you with virtio-gpu on x86? If yes, then I would not to look into the s390 code (virtio-blk and net seems to work fine). Otherwise it would be good if you could have a look. Christian