Re: [PATCH v2] fbdev: Prevent probing generic drivers if a FB is already registered
From: Daniel Vetter <hidden>
Date: 2021-11-12 16:12:26
Also in:
dri-devel, lkml
On Thu, Nov 11, 2021 at 12:39:28PM +0100, Greg Kroah-Hartman wrote:
On Thu, Nov 11, 2021 at 12:11:20PM +0100, Javier Martinez Canillas wrote:quoted
The efifb and simplefb drivers just render to a pre-allocated frame buffer and rely on the display hardware being initialized before the kernel boots. But if another driver already probed correctly and registered a fbdev, the generic drivers shouldn't be probed since an actual driver for the display hardware is already present. This is more likely to occur after commit d391c5827107 ("drivers/firmware: move x86 Generic System Framebuffers support") since the "efi-framebuffer" and "simple-framebuffer" platform devices are registered at a later time. Link: https://lore.kernel.org/r/20211110200253.rfudkt3edbd3nsyj@lahvuun/ (local) Fixes: d391c5827107 ("drivers/firmware: move x86 Generic System Framebuffers support") Reported-by: Ilya Trukhanov <redacted> Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Daniel Vetter <redacted> --- Changes in v2: - Add a Link: tag with a reference to the bug report (Thorsten Leemhuis). - Add a comment explaining why the probe fails earlier (Daniel Vetter). - Add a Fixes: tag for stable to pick the fix (Daniel Vetter).That does not mean that it will make it into the stable tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly.
Defacto your auto-picker is aggressive enough that just Fixes: is actually good enough to get it into stable :-) But yeah explicit cc: stable can't hurt. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch