From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-Id: <20120309190215.343476756@linuxfoundation.org> Date: Fri, 09 Mar 2012 11:02:18 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Alban Browaeys , Chris Wilson , Jesse Barnes Subject: [ 04/68] drm/i915: Prevent a machine hang by checking crtc->active before loading lut In-Reply-To: <20120309194409.GA2069@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alban Browaeys commit aed3f09db39596e539f90b11a5016aea4d8442e1 upstream. Before loading the lut (gamma), check the active state of intel_crtc, otherwise at least on gen2 hang ensue. This is reproducible in Xorg via: xset dpms force off then xgamma -rgamma 2.0 # freeze. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44505 Signed-off-by: Alban Browaeys Signed-off-by: Chris Wilson Reviewed-by: Jesse Barnes Signed-off-by: Jesse Barnes Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_display.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5265,7 +5265,7 @@ void intel_crtc_load_lut(struct drm_crtc int i; /* The clocks have to be on to load the palette. */ - if (!crtc->enabled) + if (!crtc->enabled || !intel_crtc->active) return; /* use legacy palette for Ironlake */