On 12/30/25 00:58, Zack Rusin wrote: > Register a devm action on the virtio device to restore the system > framebuffer (efifb/simpledrm) if the driver's probe fails after > removing the firmware framebuffer. > > Unlike PCI drivers, virtio-gpu cannot use the > devm_aperture_remove_conflicting_pci_devices() helper because the > PCI device is managed by the virtio-pci driver, not by virtio-gpu. > When virtio-gpu probe fails, the PCI device remains bound to > virtio-pci, so devm actions registered on the PCI device won't fire. > > Instead, register the sysfb restore action on the virtio device > (&vdev->dev) which will be released if virtio-gpu probe fails. > Cancel the action after successful probe since the driver is now > responsible for display output. > > This only applies to VGA devices where > aperture_remove_conflicting_pci_devices() > is called to remove the firmware framebuffer. > > Signed-off-by: Zack Rusin <[email protected]> > Cc: David Airlie <[email protected]> > Cc: Gerd Hoffmann <[email protected]> > Cc: Dmitry Osipenko <[email protected]> > Cc: Gurchetan Singh <[email protected]> > Cc: Chia-I Wu <[email protected]> > Cc: Maarten Lankhorst <[email protected]> > Cc: Maxime Ripard <[email protected]> > Cc: Thomas Zimmermann <[email protected]> > Cc: Simona Vetter <[email protected]> > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > --- > drivers/gpu/drm/virtio/virtgpu_drv.c | 29 ++++++++++++++++++++++++++++ > 1 file changed, 29 insertions(+) > > diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c > b/drivers/gpu/drm/virtio/virtgpu_drv.c > index a5ce96fb8a1d..13cc8396fc78 100644 > --- a/drivers/gpu/drm/virtio/virtgpu_drv.c > +++ b/drivers/gpu/drm/virtio/virtgpu_drv.c > @@ -30,6 +30,7 @@ > #include <linux/module.h> > #include <linux/pci.h> > #include <linux/poll.h> > +#include <linux/sysfb.h> > #include <linux/vgaarb.h> > #include <linux/wait.h> > > @@ -52,6 +53,11 @@ static int virtio_gpu_modeset = -1; > MODULE_PARM_DESC(modeset, "Disable/Enable modesetting"); > module_param_named(modeset, virtio_gpu_modeset, int, 0400); > > +static void virtio_gpu_restore_sysfb(void *unused) > +{ > + sysfb_restore(); > +} > + > static int virtio_gpu_pci_quirk(struct drm_device *dev) > { > struct pci_dev *pdev = to_pci_dev(dev->dev); > @@ -75,6 +81,7 @@ static int virtio_gpu_probe(struct virtio_device *vdev) > { > struct drm_device *dev; > int ret; > + bool sysfb_restore_registered = false; > > if (drm_firmware_drivers_only() && virtio_gpu_modeset == -1) > return -EINVAL; > @@ -97,6 +104,21 @@ static int virtio_gpu_probe(struct virtio_device *vdev) > ret = virtio_gpu_pci_quirk(dev); > if (ret) > goto err_free; > + > + /* > + * For VGA devices, register sysfb restore on the virtio device. > + * We can't use devm_aperture_remove_conflicting_pci_devices() > + * because the PCI device is managed by virtio-pci, not us. > + * Register on &vdev->dev so it fires if our probe fails. > + */ > + if (pci_is_vga(to_pci_dev(vdev->dev.parent))) { > + ret = devm_add_action_or_reset(&vdev->dev, > + virtio_gpu_restore_sysfb, > + NULL); > + if (ret) > + goto err_free; > + sysfb_restore_registered = true; > + } > } > > dma_set_max_seg_size(dev->dev, dma_max_mapping_size(dev->dev) ?: > UINT_MAX); > @@ -110,6 +132,13 @@ static int virtio_gpu_probe(struct virtio_device *vdev) > > drm_client_setup(vdev->priv, NULL); > > + /* > + * Probe succeeded - cancel sysfb restore. We're now responsible > + * for display output. > + */ > + if (sysfb_restore_registered) > + devm_remove_action(&vdev->dev, virtio_gpu_restore_sysfb, NULL); > + > return 0; > > err_deinit:
Acked-by: Dmitry Osipenko <[email protected]> -- Best regards, Dmitry
