Hi Dmitry, > Subject: Re: [RFC PATCH 0/2] Virtio-GPU suspend and resume > > On 4/19/25 02:29, dongwon....@intel.com wrote: > > From: Dongwon Kim <dongwon....@intel.com> > > > > This patch series introduces a freeze and restore mechanism for the > > virtio-gpu driver: > > > > First patch adds `virtgpu_freeze` and `virtgpu_restore` functions. > > These functions handle the deletion of virtio queues before suspension > > and their recreation during the restoration process. > > > > Second patch implements a mechanism for restoring `virtio_gpu_object` > instances. > > This is necessary because the host (QEMU) deletes all associated > > resources during the virtio-gpu reset, which occurs as part of the > > restoration > process. > > > > These changes ensure that the virtio-gpu driver can properly handle > > suspend and resume scenarios without resource loss. > > Resetting GPU by QEMU on suspend sounds like a wrong behaviour. Are you > talking about upstream QEMU? > > Could you please point at the QEMU code where it handles virtio-gpu > suspend/resume? Don't see where it happens.
[Kim, Dongwon] So I am using Ubuntu guest and whenever I suspend then resume, I see static void virtio_gpu_reset_bh(void *opaque) is being called. It is probably triggered by virtio layer but I didn't look into it. Check the video please: (https://drive.google.com/file/d/1D_JF9CzgCjzQZ3RcLAaNnUORqGj24_I9/view?usp=sharing) > > I tried to apply your kernel patches and then suspend/resume guest kernel, it > doesn't work: > > virtio_gpu_transfer_to_host_2d: no backing storage 2 > [ 22.909454] [drm:virtio_gpu_dequeue_ctrl_func] *ERROR* response > 0x1200 (command 0x105) > virtio_gpu_transfer_to_host_2d: no backing storage 2 > [ 23.169138] [drm:virtio_gpu_dequeue_ctrl_func] *ERROR* response > 0x1200 (command 0x105) [Kim, Dongwon] I will check your failing case more closely. As you know, we use virtio-gpu device only for display device, which means I tested this in that specific environment although I thought it is generic enough... > > Cc: +Alex Bennée +Akihiko Odaki > > -- > Best regards, > Dmitry [Kim, Dongwon] Thanks!
