On Tue, 07 Feb 2023, Greg Kroah-Hartman <[email protected]> wrote: > On Tue, Feb 07, 2023 at 04:33:37PM +0200, Jani Nikula wrote: >> From: Ville Syrjälä <[email protected]> >> >> CONFIG_DRM_USE_DYNAMIC_DEBUG breaks debug prints for (at least modular) >> drm drivers. The debug prints can be reinstated by manually frobbing >> /sys/module/drm/parameters/debug after the fact, but at that point the >> damage is done and all debugs from driver probe are lost. This makes >> drivers totally undebuggable. >> >> There's a more complete fix in progress [1], with further details, but >> we need this fixed in stable kernels. Mark the feature as broken and >> disable it by default, with hopes distros follow suit and disable it as >> well. >> >> [1] https://lore.kernel.org/r/[email protected] >> >> Fixes: 84ec67288c10 ("drm_print: wrap drm_*_dbg in dyndbg descriptor factory >> macro") >> Cc: Jim Cromie <[email protected]> >> Cc: Greg Kroah-Hartman <[email protected]> >> Cc: Maarten Lankhorst <[email protected]> >> Cc: Maxime Ripard <[email protected]> >> Cc: Thomas Zimmermann <[email protected]> >> Cc: David Airlie <[email protected]> >> Cc: Daniel Vetter <[email protected]> >> Cc: [email protected] >> Cc: <[email protected]> # v6.1+ >> Signed-off-by: Ville Syrjälä <[email protected]> >> Signed-off-by: Jani Nikula <[email protected]> >> --- >> drivers/gpu/drm/Kconfig | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig >> index f42d4c6a19f2..dc0f94f02a82 100644 >> --- a/drivers/gpu/drm/Kconfig >> +++ b/drivers/gpu/drm/Kconfig >> @@ -52,7 +52,8 @@ config DRM_DEBUG_MM >> >> config DRM_USE_DYNAMIC_DEBUG >> bool "use dynamic debug to implement drm.debug" >> - default y >> + default n >> + depends on BROKEN >> depends on DRM >> depends on DYNAMIC_DEBUG || DYNAMIC_DEBUG_CORE >> depends on JUMP_LABEL > > Acked-by: Greg Kroah-Hartman <[email protected]>
Thanks Greg, any more acks from anyone? Maxime, since there's going to be an -rc8, I suggest taking this via drm-misc-fixes. Is that okay with you? (You're doing drm-misc-fixes this round, right?) BR, Jani. -- Jani Nikula, Intel Open Source Graphics Center
