mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
![]() When the usual fbcon legacy options are enabled we have ->register_framebuffer ->fb notifier chain calls into fbcon ->fbcon sets up console on new fbi ->fbi->set_par ->drm_fb_helper_set_par exercises full kms api And because of locking inversion hilarity all of register_framebuffer is done with the console lock held. Which means that the first time on driver load we exercise _all_ the kms code (all probe paths and modeset paths for everything connected) is under the console lock. That means if anything goes belly-up in that big pile of code nothing ever reaches logfiles (and the machine is dead). Usual tactic to debug that is to temporarily remove those console_lock calls to be able to capture backtraces. I'm fed up writing this patch and recompiling kernels. Hence this patch here to add an unsafe, kernel-taining option to do this at runtime. Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: linux-fbdev@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> |
||
---|---|---|
.. | ||
backlight | ||
console | ||
fbdev | ||
logo | ||
display_timing.c | ||
hdmi.c | ||
Kconfig | ||
Makefile | ||
of_display_timing.c | ||
of_videomode.c | ||
vgastate.c | ||
videomode.c |