Hi On Thu, Aug 17, 2023 at 8:29 PM Kim, Dongwon <dongwon....@intel.com> wrote: > > Ok, this regression happened not just because of renaming. Originally > width and height were representing the size of whole surface that guest > shares while scanout width and height are for the each scanout. We > realized backing_width/height are more commonly used to specify the size > of the whole guest surface so put them in the place of width/height then > replaced scanout_width/height as well with normal width/height. > > On 8/16/2023 3:31 PM, Philippe Mathieu-Daudé wrote: > > On 16/8/23 23:55, Alex Williamson wrote: > >> The below referenced commit renames scanout_width/height to > >> backing_width/height, but also promotes these fields in various portions > >> of the egl interface. Meanwhile vfio dmabuf support has never used the > >> previous scanout fields and is therefore missed in the update. This > >> results in a black screen when transitioning from ramfb to dmabuf > >> display > >> when using Intel vGPU with these features. > > > > Referenced commit isn't trivial. Maybe because it is too late here. > > I'd have tried to split it. Anyhow, too late (again). > > > > Is vhost-user-gpu also affected? (see VHOST_USER_GPU_DMABUF_SCANOUT > > in vhost_user_gpu_handle_display()). > > Yeah, backing_width/height should be programmed with plane.width/height > as well in vhost_user_gpu_handle_display(). > > Link: https://lists.gnu.org/archive/html/qemu-devel/2023-08/msg02726.html > >> Fixes: 9ac06df8b684 ("virtio-gpu-udmabuf: correct naming of > >> QemuDmaBuf size properties") > >> Signed-off-by: Alex Williamson <alex.william...@redhat.com> > >> --- > >> > >> This fixes a regression in dmabuf/EGL support for Intel GVT-g and > >> potentially the mbochs mdev driver as well. Once validated by those > >> that understand dmabuf/EGL integration, I'd welcome QEMU maintainers to > >> take this directly for v8.1 or queue it as soon as possible for v8.1.1. > >> > >> hw/vfio/display.c | 2 ++ > >> 1 file changed, 2 insertions(+) > >> > >> diff --git a/hw/vfio/display.c b/hw/vfio/display.c > >> index bec864f482f4..837d9e6a309e 100644 > >> --- a/hw/vfio/display.c > >> +++ b/hw/vfio/display.c > >> @@ -243,6 +243,8 @@ static VFIODMABuf > >> *vfio_display_get_dmabuf(VFIOPCIDevice *vdev, > >> dmabuf->dmabuf_id = plane.dmabuf_id; > >> dmabuf->buf.width = plane.width; > >> dmabuf->buf.height = plane.height; > > One thing to note here is the normal width and height in the QemuDmaBuf > are of a scanout, which could be just a partial area of the guest plane > here. So we should not use those as normal width and height of the > QemuDmaBuf unless it is guaranteed the given guest surface (plane in > this case) is always of single display's. > > https://lists.gnu.org/archive/html/qemu-devel/2021-09/msg04737.html > > >> + dmabuf->buf.backing_width = plane.width; > >> + dmabuf->buf.backing_height = plane.height; > >> dmabuf->buf.stride = plane.stride; > >> dmabuf->buf.fourcc = plane.drm_format; > >> dmabuf->buf.modifier = plane.drm_format_mod; > > >
I agree with what Kim said. Alex, are you sending a new patch? thanks -- Marc-André Lureau
