Re: [PATCH v2 0/2] Improve vfio-pci primary GPU assignment behavior

From: Laszlo Ersek
Date: Mon Jun 20 2022 - 07:43:47 EST


On 06/16/22 22:38, Alex Williamson wrote:
> When assigning a primary graphics device to VM through vfio-pci device
> assignment, users often prevent binding of the native PCI graphics
> driver to avoid device initialization conflicts, however firmware
> console drivers may still be attached to the device which can often be
> cumbersome to manually unbind or exclude via cmdline options.
>
> This series proposes to move the DRM aperture helpers out to
> drivers/video/ to make it more accessible to drivers like vfio-pci,
> which have neither dependencies on DRM code nor a struct drm_driver
> to present to existing interfaces. vfio-pci can then trivially call
> into the aperture helpers to remove conflicting drivers, rather than
> open coding it ourselves as was proposed with a new symbol export in
> v1 of this series[1].
>
> Thanks to Thomas for splitting out the aperture code with new
> documentation.
>
> Thomas had proposed this going through the vfio tree with appropriate
> stakeholder acks, that's fine with me, but I'm also open to it going
> through the DRM tree given that the vfio-pci-core change is even more
> trivial now and the bulk of the changes are DRM/video paths. Thanks,
>
> Alex
>
> [1]https://lore.kernel.org/all/165453797543.3592816.6381793341352595461.stgit@omen/
>
> ---
>
> Alex Williamson (1):
> vfio/pci: Remove console drivers
>
> Thomas Zimmermann (1):
> drm: Implement DRM aperture helpers under video/
>
>
> Documentation/driver-api/aperture.rst | 13 +
> Documentation/driver-api/index.rst | 1 +
> drivers/gpu/drm/drm_aperture.c | 174 +------------
> drivers/gpu/drm/tiny/Kconfig | 1 +
> drivers/vfio/pci/vfio_pci_core.c | 5 +
> drivers/video/Kconfig | 6 +
> drivers/video/Makefile | 2 +
> drivers/video/aperture.c | 340 ++++++++++++++++++++++++++
> drivers/video/console/Kconfig | 1 +
> drivers/video/fbdev/Kconfig | 7 +-
> include/linux/aperture.h | 56 +++++
> 11 files changed, 440 insertions(+), 166 deletions(-)
> create mode 100644 Documentation/driver-api/aperture.rst
> create mode 100644 drivers/video/aperture.c
> create mode 100644 include/linux/aperture.h
>

series
Tested-by: Laszlo Ersek <lersek@xxxxxxxxxx>

(on top of Fedora's 5.18.5-100.fc35.x86_64)

Thanks,
Laszlo