From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: [PATCH] drm/i915: Sanitize the enable_ppgtt module option once Date: Fri, 25 Apr 2014 16:11:52 +0300 Message-ID: <874n1hv9if.fsf@intel.com> References: <1398197870-20488-1-git-send-email-daniel.vetter@ffwll.ch> <87r44oh25h.fsf@intel.com> <20140423180217.GE10722@phenom.ffwll.local> <87mwfbvwer.fsf@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id 77FB56EE7D for ; Fri, 25 Apr 2014 06:11:55 -0700 (PDT) In-Reply-To: <87mwfbvwer.fsf@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Daniel Vetter Cc: Daniel Vetter , Intel Graphics Development , Ben Widawsky , Alessandro Suardi List-Id: intel-gfx@lists.freedesktop.org On Thu, 24 Apr 2014, Jani Nikula wrote: > On Wed, 23 Apr 2014, Daniel Vetter wrote: >> On Wed, Apr 23, 2014 at 11:37:46AM +0300, Jani Nikula wrote: >>> On Tue, 22 Apr 2014, Daniel Vetter wrote: >>> > Otherwise we'll end up spamming dmesg on every context creation on snb >>> > with vt-d enabled. This regression was introduced in >>> > >>> > commit 246cbfb5fb9a1ca0997fbb135464c1ff5bb9c549 >>> > Author: Ben Widawsky >>> > Date: Fri Dec 6 14:11:14 2013 -0800 >>> > >>> > drm/i915: Reorganize intel_enable_ppgtt >>> > >>> > References: https://lkml.org/lkml/2014/4/17/599 >>> > Cc: Alessandro Suardi >>> > Cc: Ben Widawsky >>> > Signed-off-by: Daniel Vetter >>> > --- >>> > drivers/gpu/drm/i915/i915_gem_gtt.c | 26 +++++++++++++++++++------- >>> > 1 file changed, 19 insertions(+), 7 deletions(-) >>> > >>> > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c >>> > index 0d514ff9b94c..47491c4a1181 100644 >>> > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c >>> > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c >>> > @@ -34,25 +34,35 @@ static void gen8_setup_private_ppat(struct drm_i915_private *dev_priv); >>> > >>> > bool intel_enable_ppgtt(struct drm_device *dev, bool full) >>> > { >>> > - if (i915.enable_ppgtt == 0 || !HAS_ALIASING_PPGTT(dev)) >>> > + if (i915.enable_ppgtt == 0) >>> > return false; >>> > >>> > if (i915.enable_ppgtt == 1 && full) >>> > return false; >>> > >>> > + return true; >>> > +} >>> > + >>> > +static int sanitize_enable_ppgtt(struct drm_device *dev, int enable_ppgtt) >>> > +{ >>> > + if (enable_ppgtt == 0 || !HAS_ALIASING_PPGTT(dev)) >>> > + return 0; >>> > + >>> > + if (i915.enable_ppgtt == 1) >>> > + return 1; >>> > + >>> > + if (i915.enable_ppgtt == 2 && HAS_PPGTT(dev)) >>> > + return 2; >>> >>> You should probably either pass enable_ppgtt as parameter and use that >>> exclusively, or not pass it and refer to i915.enable_ppgtt directly, but >>> not mix them. >> >> New patch on its way with Chris' comments also applied. >>> >>> > + >>> > #ifdef CONFIG_INTEL_IOMMU >>> > /* Disable ppgtt on SNB if VT-d is on. */ >>> > if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped) { >>> > DRM_INFO("Disabling PPGTT because VT-d is on\n"); >>> > - return false; >>> > + return 0; >>> > } >>> > #endif >>> > >>> > - /* Full ppgtt disabled by default for now due to issues. */ >>> > - if (full) >>> > - return HAS_PPGTT(dev) && (i915.enable_ppgtt == 2); >>> > - else >>> > - return HAS_ALIASING_PPGTT(dev); >>> > + return HAS_ALIASING_PPGTT(dev) ? 1 : 0; >>> >>> >>> This conflicts in -fixes due to >>> commit 8d214b7d9c45f4af23ce41b2bc74f79c44f760de >>> Author: Ben Widawsky >>> Date: Mon Mar 24 18:06:00 2014 -0700 >>> >>> drm/i915: Allow full PPGTT with param override >>> >>> Should I incorporate that in the conflict resolution for simplicity, >>> letting 3.15 users also play with full ppgtt with the module param? >> >> Yeah I guess it's easiest to just cherry-pick that one to -fixes, too. >> -Daniel > > Pushed v2 to -fixes, along with "drm/i915: Allow full PPGTT with param > override". Thanks for the patch and review. And yanked out again due to [1]. Back to the drawing board. Please also add a ppgtt sanity check BUG_ON before returning true from intel_enable_ppgtt(). BR, Jani. [1] https://bugs.freedesktop.org/show_bug.cgi?id=77916 -- Jani Nikula, Intel Open Source Technology Center