• Daniel Vetter's avatar
    drm/fb-helper: Give up on kgdb for atomic drivers · 9c79e0b1
    Daniel Vetter authored
    It just doesn't work. It probably stopped working way, way before that
    (e.g. i915 grabbed random mutexes all over in modeset code at least
    since gen6), but with atomic and all the ww_mutex stuff it's indeed
    hopeless.
    
    Remove ->mode_set_base_atomic from the 2 atomic drivers (i915 and
    nouveau) that still had one (both had dummy implementations already
    anyway), and shunt atomic drivers in the helpers debug_enter/leave
    functions.
    
    I'll leave the code in for radeon and amdgpu, but I think as soon as
    amdgpu is atomic we should think about just ripping it out. Only
    having it around for radeon and pre-nv50 is rather pointless. This
    would also allow us to nuke all that code from fbdev.
    
    Funny part is that _all_ kms drivers set this hook, despite that no
    one else provides the required ->mode_set_base_atomic implementation.
    
    The reason I'm jumping on this is that I want to wire up a full
    acquire ctx for the benefit of atomic drivers, everywhere. And the
    debug_enter/leave implementations call ->gamma_set. And there's just
    no way ever we can create an acquire_ctx in the nmi context of kgdb.
    
    Cc: Ben Skeggs <bskeggs@redhat.com>
    Cc: Alex Deucher <alexander.deucher@amd.com>
    Reviewed-by: default avatarMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
    Acked-by: default avatarAlex Deucher <alexander.deucher@amd.com>
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@intel.com>
    Link: http://patchwork.freedesktop.org/patch/msgid/20170403083304.9083-11-daniel.vetter@ffwll.ch
    9c79e0b1
drm_fb_helper.c 67.3 KB