Re: [PATCH RFC drm-next 0/1] Add support for drm_panic

[Thomas Zimmermann]

Hi

Am 02.04.25 um 15:52 schrieb Ryosuke Yasuoka:
> On Wed, Apr 2, 2025 at 6:45 PM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:
> > Hi
> >
> > Am 02.04.25 um 10:43 schrieb Ryosuke Yasuoka:
> > > This patch adds drm_panic support for hyperv-drm driver. This function
> > > works but it's still needed to brush up. Let me hear your opinions.
> > >
> > > Once kernel panic occurs we expect to see a panic screen. However, to
> > > see the screen, I need to close/re-open the graphic console client
> > > window. As the panic screen shows correctly in the small preview
> > > window in Hyper-V manager and debugfs API for drm_panic works correctly,
> > > I think kernel needs to send signal to Hyper-V host that the console
> > > client refreshes, but I have no idea what kind of signal is needed.
> > >
> > > This patch is tested on Hyper-V 2022.
> > >
> > > Ryosuke Yasuoka (1):
> > >     drm/hyperv: Add support for drm_panic
> > >
> > >    drivers/gpu/drm/drm_simple_kms_helper.c     | 26 +++++++++++++
> > >    drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 42 +++++++++++++++++++++
> > >    include/drm/drm_simple_kms_helper.h         | 22 +++++++++++
> > No changes to simple_kms_helper please. This is obsolete and should go
> > away. Just put everything into hyperv_drm.
> OK. Maybe it will work without any modification in simple_kms_helper if we can
> call the pipe->funcs from draw_panic_plane() like drm_plane_helper_funcs.

No problem about that. Feel free to open-code everything that you need 
in the hyperv driver.

> Currently, the hyperv_drm is implemented with a simple display pipeline.
> The pipeline control functions are in pipe->funcs and they will call via
> drm_simple_kms_palne_helper_funcs. And these helper functions will
> be called by drm_panic_plane().

Someone should update the hyperv driver to not use simple pipe.

Best regards
Thomas

> Thank you for your comment.
> Ryosuke
>
> > Best regards
> > Thomas
> >
> > >    3 files changed, 90 insertions(+)
> > >
> > >
> > > base-commit: cf05922d63e2ae6a9b1b52ff5236a44c3b29f78c
> > --
> > --
> > Thomas Zimmermann
> > Graphics Driver Developer
> > SUSE Software Solutions Germany GmbH
> > Frankenstrasse 146, 90461 Nuernberg, Germany
> > GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
> > HRB 36809 (AG Nuernberg)

--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)