Jocelyn Falempe <jfalempe@xxxxxxxxxx> writes: > On 16/06/2024 14:43, Javier Martinez Canillas wrote: >> Jocelyn Falempe <jfalempe@xxxxxxxxxx> writes: >> >> Hello Jocelyn, >> >>> The race condition between fbcon and drm_panic can only occurs if >>> VT_CONSOLE is set. So update drm_panic dependency accordingly. >>> This will make it easier for Linux distributions to enable drm_panic >>> by disabling VT_CONSOLE, and keeping fbcon terminal. >>> The only drawback is that fbcon won't display the boot kmsg, so it >>> should rely on userspace to do that. >>> At least plymouth already handle this case with >>> https://gitlab.freedesktop.org/plymouth/plymouth/-/merge_requests/224 >>> >>> Suggested-by: Daniel Vetter <daniel.vetter@xxxxxxxx> >>> Signed-off-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx> >>> --- >>> drivers/gpu/drm/Kconfig | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig >>> index a9df94291622..f5c989aed7e9 100644 >>> --- a/drivers/gpu/drm/Kconfig >>> +++ b/drivers/gpu/drm/Kconfig >>> @@ -107,7 +107,7 @@ config DRM_KMS_HELPER >>> >>> config DRM_PANIC >>> bool "Display a user-friendly message when a kernel panic occurs" >>> - depends on DRM && !FRAMEBUFFER_CONSOLE >>> + depends on DRM && !(FRAMEBUFFER_CONSOLE && VT_CONSOLE) >> >> I thought the idea was to only make it depend on !VT_CONSOLE, so that >> distros could also enable fbcon / VT but prevent the race condition to >> happen due the VT not being a system console for the kernel to print >> messages ? > > Yes, but when writing the patch, I thought that if you have VT_CONSOLE=y > and FRAMEBUFFER_CONSOLE=n, then there won't be any race condition, and > drm_panic can be enabled safely. Ah, I see what you mean. > I don't know if that really matters, and if VT_CONSOLE has any usage > apart from fbcon. > Right. I don't know... -- Best regards, Javier Martinez Canillas Core Platforms Red Hat
