Re: virtio-gpu: Hang on shutdown after suspend/resume with virtio

[Christian Borntraeger <borntraeger@de.ibm.com>]

On 03/13/2018 01:41 PM, Christian Borntraeger wrote:
> 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
  now
> it would be good if you could have a look.

I just checked. It seems that virtio-gpu has no freeze/restore callbacks. Is there
some work planned to implement the power callbacks for virtio-gpu?