From: Michel Dänzer <michel@xxxxxxxxxxx> This patch has been added to the 3.12 stable tree. If you have any objections, please let us know. =============== NOTE: This patch only applies to 4.5.y or older kernels. With newer kernels, this problem cannot happen because the driver now uses drm_crtc_vblank_on/off instead of drm_vblank_pre/post_modeset[0]. I consider this patch safer for older kernels than backporting the API change, because drm_crtc_vblank_on/off had various issues in older kernels, and I'm not sure all fixes for those have been backported to all stable branches where this patch could be applied. --------------------- Fixes the vblank interrupt being disabled when it should be on, which can cause at least the following symptoms: * Hangs when running 'xset dpms force off' in a GNOME session with gnome-shell using DRI2. * RandR 1.4 slave outputs freezing with garbage displayed using xf86-video-ati 7.8.0 or newer. [0] See upstream commit: commit 777e3cbc791f131806d9bf24b3325637c7fc228d Author: Daniel Vetter <daniel.vetter@xxxxxxxx> Date: Thu Jan 21 11:08:57 2016 +0100 drm/radeon: Switch to drm_vblank_on/off Reported-and-Tested-by: Max Staudt <mstaudt@xxxxxxx> Reviewed-by: Daniel Vetter <daniel@xxxxxxxx> Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Michel Dänzer <michel.daenzer@xxxxxxx> --- drivers/gpu/drm/radeon/atombios_crtc.c | 2 ++ drivers/gpu/drm/radeon/radeon_legacy_crtc.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index d988fff65ee5..ae2e03ea2371 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -277,6 +277,8 @@ void atombios_crtc_dpms(struct drm_crtc *crtc, int mode) atombios_enable_crtc_memreq(crtc, ATOM_ENABLE); atombios_blank_crtc(crtc, ATOM_DISABLE); drm_vblank_post_modeset(dev, radeon_crtc->crtc_id); + /* Make sure vblank interrupt is still enabled if needed */ + radeon_irq_set(rdev); radeon_crtc_load_lut(crtc); break; case DRM_MODE_DPMS_STANDBY: diff --git a/drivers/gpu/drm/radeon/radeon_legacy_crtc.c b/drivers/gpu/drm/radeon/radeon_legacy_crtc.c index bc73021d3596..ae0d7b1cb9aa 100644 --- a/drivers/gpu/drm/radeon/radeon_legacy_crtc.c +++ b/drivers/gpu/drm/radeon/radeon_legacy_crtc.c @@ -331,6 +331,8 @@ static void radeon_crtc_dpms(struct drm_crtc *crtc, int mode) WREG32_P(RADEON_CRTC_EXT_CNTL, crtc_ext_cntl, ~(mask | crtc_ext_cntl)); } drm_vblank_post_modeset(dev, radeon_crtc->crtc_id); + /* Make sure vblank interrupt is still enabled if needed */ + radeon_irq_set(rdev); radeon_crtc_load_lut(crtc); break; case DRM_MODE_DPMS_STANDBY: -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html