Hello Geert, On 11/16/21 10:43, Geert Uytterhoeven wrote: [snip] >> >> So this is already a fragile solution and $SUBJECT doesn't make things worse >> IMO. Since not having something like this can lead to issues as reported by: >> >> https://lore.kernel.org/all/20211110200253.rfudkt3edbd3nsyj@lahvuun/ >> >> We could probably do some smarter here by providing a function that checks >> if the registered fbdev drivers matches the aperture base. But I'm unsure >> if that's worth it. After all, fbdev drivers are likely to be disabled by >> most distros soon now that we have the simpledrm driver. > > Checking the aperture base is what was done in all other cases of > preventing generic (fbdev) drivers from stepping on specific drivers' > toes... > Ok, I can re-spin the patch checking if the aperture ranges overlap. There's an apertures_overlap() function in drivers/video/fbdev/core/fbmem.c that can be exported for fbdev drivers to use. Another option is to just say that DRM drivers should be built as a module if the {efi,simple}fb driver are built-in. Best regards, -- Javier Martinez Canillas Linux Engineering Red Hat
