[v3,0/3] Improve vfio-pci primary GPU assignment behavior

Message

Thomas Zimmermann June 22, 2022, 2:01 p.m. UTC

(I'm taking over this patchset from Alex, [1] as we agreed that it should
go through the drm-misc tree.)

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. [2]

v3:
	* add aperture_ prefix to all interfaces (Javier)
	* improved documentation (Javier)
	* update MAINTAINERS [3] and add aperture helpers

[1] https://lore.kernel.org/all/165541020563.1955826.16350888595945658159.stgit@omen/
[2] https://lore.kernel.org/all/165453797543.3592816.6381793341352595461.stgit@omen/
[3] https://lore.kernel.org/all/[e-mail]/

Alex Williamson (1):
  vfio/pci: Remove console drivers

Thomas Zimmermann (2):
  MAINTAINERS: Broaden scope of simpledrm entry
  drm: Implement DRM aperture helpers under video/

 Documentation/driver-api/aperture.rst |  13 +
 Documentation/driver-api/index.rst    |   1 +
 MAINTAINERS                           |   6 +-
 drivers/gpu/drm/drm_aperture.c        | 178 +------------
 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              | 351 ++++++++++++++++++++++++++
 drivers/video/console/Kconfig         |   1 +
 drivers/video/fbdev/Kconfig           |   7 +-
 include/linux/aperture.h              |  56 ++++
 12 files changed, 456 insertions(+), 171 deletions(-)
 create mode 100644 Documentation/driver-api/aperture.rst
 create mode 100644 drivers/video/aperture.c
 create mode 100644 include/linux/aperture.h


base-commit: 7025c1f111b7a057243de45bd56c14b906242a53

Comments

Thomas Zimmermann July 4, 2022, 7:10 a.m. UTC | #1

Hi,

this patchset has meanwhile reached drm-next and should go into Linux v5.20.

 
https://cgit.freedesktop.org/drm/drm/commit/?id=d173780620792c725506b0f3c5ec52c7fbac1db0

Best regards
Thomas

Am 22.06.22 um 16:01 schrieb Thomas Zimmermann:
> (I'm taking over this patchset from Alex, [1] as we agreed that it should
> go through the drm-misc tree.)
> 
> 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. [2]
> 
> v3:
> 	* add aperture_ prefix to all interfaces (Javier)
> 	* improved documentation (Javier)
> 	* update MAINTAINERS [3] and add aperture helpers
> 
> [1] https://lore.kernel.org/all/165541020563.1955826.16350888595945658159.stgit@omen/
> [2] https://lore.kernel.org/all/165453797543.3592816.6381793341352595461.stgit@omen/
> [3] https://lore.kernel.org/all/[e-mail]/
> 
> Alex Williamson (1):
>    vfio/pci: Remove console drivers
> 
> Thomas Zimmermann (2):
>    MAINTAINERS: Broaden scope of simpledrm entry
>    drm: Implement DRM aperture helpers under video/
> 
>   Documentation/driver-api/aperture.rst |  13 +
>   Documentation/driver-api/index.rst    |   1 +
>   MAINTAINERS                           |   6 +-
>   drivers/gpu/drm/drm_aperture.c        | 178 +------------
>   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              | 351 ++++++++++++++++++++++++++
>   drivers/video/console/Kconfig         |   1 +
>   drivers/video/fbdev/Kconfig           |   7 +-
>   include/linux/aperture.h              |  56 ++++
>   12 files changed, 456 insertions(+), 171 deletions(-)
>   create mode 100644 Documentation/driver-api/aperture.rst
>   create mode 100644 drivers/video/aperture.c
>   create mode 100644 include/linux/aperture.h
> 
> 
> base-commit: 7025c1f111b7a057243de45bd56c14b906242a53