On Wed, Nov 26, 2025 at 02:32:32PM +0100, Thomas Zimmermann wrote: > Hi > > Am 26.11.25 um 13:19 schrieb Daniel Thompson: > > On Tue, Nov 25, 2025 at 07:26:33AM -0800, Doug Anderson wrote: > > > On Tue, Nov 25, 2025 at 5:06 AM Thomas Zimmermann <[email protected]> > > > wrote: > > > > <snip> > > > > Therefore remove the remaining support for kdb from the DRM drivers > > > > and from DRM fbdev emulation. Also remove the hooks from fbdev, as > > > > there are no fbdev drivers with kdb support. > > > > > > > > If we ever want to address kdb support within DRM drivers, a place to > > > > start would be the scanout buffers used by DRM's panic screen. These > > > > use the current display mode. They can be written and flushed without > > > > mode setting involved. > > > > > > > > Note: kdb over serial lines is not affected by this series and continues > > > > to work as before. > > > > > > > > Thomas Zimmermann (5): > > > > drm/amdgpu: Do not implement mode_set_base_atomic callback > > > > drm/nouveau: Do not implement mode_set_base_atomic callback > > > > drm/radeon: Do not implement mode_set_base_atomic callback > > > > drm/fbdev-helper: Remove drm_fb_helper_debug_enter/_leave() > > > > fbcon: Remove fb_debug_enter/_leave from struct fb_ops > > > Personally, I've never worked with kdb over anything other than > > > serial, so this won't bother any of my normal workflows. That being > > > said, at least as of a year ago someone on the lists was talking about > > > using kdb with a keyboard and (presumably) a display. You can see a > > > thread here: > > > > > > http://lore.kernel.org/r/[email protected] > > > > > > Daniel may also have comments here? > > TL;DR - I'm pretty relaxed about these changes... but I'd like > > to know how to test the changes. > > > > Like Doug I only really use kdb via serial but, since I'm maintain > > the thing I do occasionally test kdb works on the qemu console. I don't > > do it very often though because it's a manual test! > > > > I'd assume that will still work since it won't involve any of the > > drivers above. I'm afraid I can't double check that since patch 4 > > doesn't apply cleanly in v6.18-rc7 (nor to linux-next... and neither > > does the base-commit appear in linux-next). > > To test its effects, ignore this series and simply clear the two calbacks at > [1]. This is where the debugger invokes fbcon. The series removes their > implementation in the final patch. > > [1] > https://elixir.bootlin.com/linux/v6.17.9/source/drivers/video/fbdev/core/fbcon.c#L3202
Thanks. Explanation in original cover letter was great and there's certainly been no harm to QEMU. Acked-by: Daniel Thompson (RISCstar) <[email protected]> Daniel.
