From 8b6124a633d8095b0c8364f585edff9c59568a96 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 30 Jan 2014 14:38:16 +0000 Subject: [PATCH] drm/i915: Don't access snooped pages through the GTT (even for error capture) MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit We want to use the GTT for reading back objects upon an error so that we have exactly the information that the GPU saw. However, it is verboten to access snoopable pages through the GTT and causes my PineView GPU to throw a page fault instead. This has not been a problem in the past as we only dumped ringbuffers and batchbuffers, both of which must be not snooped. However, the introduction of HWS page dumping leads to a read of a snooped object through the GTT. This was introduced by commit f3ce3821393e31a3f1a8ca6c24eb2d735a428445 Author: Chris Wilson Date: Thu Jan 23 22:40:36 2014 +0000 drm/i915: Include HW status page in error capture Signed-off-by: Chris Wilson Reviewed-by: Ville Syrjälä [danvet:s/uncached/not snooped/ for one case in the commit message as requested by Chris.] Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_gpu_error.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index 64591ca7fa3e..94542d498296 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -536,7 +536,8 @@ i915_error_object_create_sized(struct drm_i915_private *dev_priv, goto unwind; local_irq_save(flags); - if (reloc_offset < dev_priv->gtt.mappable_end && + if (src->cache_level == I915_CACHE_NONE && + reloc_offset < dev_priv->gtt.mappable_end && src->has_global_gtt_mapping && i915_is_ggtt(vm)) { void __iomem *s; -- 2.34.1