From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161772Ab2GLWkO (ORCPT ); Thu, 12 Jul 2012 18:40:14 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:44509 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161755Ab2GLWkF (ORCPT ); Thu, 12 Jul 2012 18:40:05 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg KH , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Ben Skeggs , Dave Airlie Subject: [ 072/187] drm/nouveau/fbcon: using nv_two_heads is not a good idea Date: Thu, 12 Jul 2012 15:33:48 -0700 Message-Id: <20120712191529.079783605@linuxfoundation.org> X-Mailer: git-send-email 1.7.10.1.362.g242cab3 In-Reply-To: <20120712191522.742634173@linuxfoundation.org> References: <20120712192421.GA28926@kroah.com> <20120712191522.742634173@linuxfoundation.org> User-Agent: quilt/0.60-20.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg KH 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ben Skeggs commit 9bd0c15fcfb42f6245447c53347d65ad9e72080b upstream. nv_two_heads() was never meant to be used outside of pre-nv50 code. The code checks for >= NV_10 for 2 CRTCs, then downgrades a few specific chipsets to 1 CRTC based on (pci_device & 0x0ff0). The breakage example seen is on GTX 560Ti, with a pciid of 0x1200, which gets detected as an NV20 (0x020x) with 1 CRTC by nv_two_heads(), causing memory corruption because there's actually 2 CRTCs.. This switches fbcon to use the CRTC count directly from the mode_config structure, which will also fix the same issue on Kepler boards which have 4 CRTCs. Signed-off-by: Ben Skeggs Signed-off-by: Dave Airlie Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/nouveau/nouveau_fbcon.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c +++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c @@ -497,7 +497,7 @@ int nouveau_fbcon_init(struct drm_device nfbdev->helper.funcs = &nouveau_fbcon_helper_funcs; ret = drm_fb_helper_init(dev, &nfbdev->helper, - nv_two_heads(dev) ? 2 : 1, 4); + dev->mode_config.num_crtc, 4); if (ret) { kfree(nfbdev); return ret;