From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Widawsky Subject: [PATCH 39/48] drm/i915: Do not allow buffers at offset 0 Date: Fri, 6 Dec 2013 14:11:24 -0800 Message-ID: <1386367941-7131-39-git-send-email-benjamin.widawsky@intel.com> References: <20131206215521.GA6922@bwidawsk.net> <1386367941-7131-1-git-send-email-benjamin.widawsky@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail.bwidawsk.net (bwidawsk.net [166.78.191.112]) by gabe.freedesktop.org (Postfix) with ESMTP id 1435BFAB64 for ; Fri, 6 Dec 2013 14:15:19 -0800 (PST) In-Reply-To: <1386367941-7131-1-git-send-email-benjamin.widawsky@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org To: Intel GFX Cc: Ben Widawsky , Ben Widawsky List-Id: intel-gfx@lists.freedesktop.org This is primarily a band aid for an unexplainable error in gem_reloc_vs_gpu/forked-faulting-reloc-thrashing. Essentially as soon as a relocated buffer (which had a non-zero presumed offset) moved to offset 0, something goes bad. Since I have been unable to solve this, and potentially this is a good thing to do anyway, since many things can accidentally write to offset 0, why not? Signed-off-by: Ben Widawsky --- drivers/gpu/drm/i915/i915_gem.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index e6d7b4c..a9cabff 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -3280,9 +3280,11 @@ i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj, WARN_ON(!list_is_singular(&obj->vma_list)); search_free: + /* FIXME: Some tests are failing when they receive a reloc of 0. To + * prevent this, we simply don't allow the 0th offset. */ ret = drm_mm_insert_node_in_range_generic(&vm->mm, &vma->node, size, alignment, - obj->cache_level, 0, gtt_max, + obj->cache_level, 1, gtt_max, DRM_MM_SEARCH_DEFAULT); if (ret) { ret = i915_gem_evict_something(dev, vm, size, alignment, -- 1.8.4.2