From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out4-smtp.messagingengine.com ([66.111.4.28]:40914 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751638AbcIIQBN (ORCPT ); Fri, 9 Sep 2016 12:01:13 -0400 Subject: FAILED: patch "[PATCH] drm/i915: Unconditionally flush any chipset buffers before" failed to apply to 4.7-stable tree To: chris@chris-wilson.co.uk, akash.goel@intel.com, ccr@tnsp.org, daniel.vetter@ffwll.ch, jani.nikula@intel.com, mika.kuoppala@intel.com, tvrtko.ursulin@linux.intel.com Cc: From: Date: Fri, 09 Sep 2016 18:01:19 +0200 Message-ID: <1473436879143134@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: The patch below does not apply to the 4.7-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >>From dcd79934b0dd803fdb29216fbd6f4a899a66f466 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 18 Aug 2016 17:16:40 +0100 Subject: [PATCH] drm/i915: Unconditionally flush any chipset buffers before execbuf MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If userspace is asynchronously streaming into the batch or other execobjects, we may not flush those writes along with a change in cache domain (as there is no change). Therefore those writes may end up in internal chipset buffers and not visible to the GPU upon execution. We must issue a flush command or otherwise we encounter incoherency in the batchbuffers and the GPU executing invalid commands (i.e. hanging) quite regularly. v2: Throw a paranoid wmb() into the general flush so that we remain consistent with before. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=90841 Fixes: 1816f9236303 ("drm/i915: Support creation of unbound wc user...") Signed-off-by: Chris Wilson Cc: Akash Goel Cc: Daniel Vetter Cc: Tvrtko Ursulin Tested-by: Matti Hämäläinen Cc: stable@vger.kernel.org Reviewed-by: Mika Kuoppala Link: http://patchwork.freedesktop.org/patch/msgid/20160818161718.27187-1-chris@chris-wilson.co.uk (cherry picked from commit 600f436801deae65e48404847b61c89b4944e355) Signed-off-by: Jani Nikula diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 20fe9d52e256..3ca674e9c105 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3591,6 +3591,7 @@ int i915_gem_evict_vm(struct i915_address_space *vm, bool do_idle); /* belongs in i915_gem_gtt.h */ static inline void i915_gem_chipset_flush(struct drm_i915_private *dev_priv) { + wmb(); if (INTEL_GEN(dev_priv) < 6) intel_gtt_chipset_flush(); } diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 1978633e7549..b35e5b6475b2 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -943,8 +943,6 @@ i915_gem_execbuffer_move_to_gpu(struct drm_i915_gem_request *req, { const unsigned other_rings = ~intel_engine_flag(req->engine); struct i915_vma *vma; - uint32_t flush_domains = 0; - bool flush_chipset = false; int ret; list_for_each_entry(vma, vmas, exec_list) { @@ -957,16 +955,11 @@ i915_gem_execbuffer_move_to_gpu(struct drm_i915_gem_request *req, } if (obj->base.write_domain & I915_GEM_DOMAIN_CPU) - flush_chipset |= i915_gem_clflush_object(obj, false); - - flush_domains |= obj->base.write_domain; + i915_gem_clflush_object(obj, false); } - if (flush_chipset) - i915_gem_chipset_flush(req->engine->i915); - - if (flush_domains & I915_GEM_DOMAIN_GTT) - wmb(); + /* Unconditionally flush any chipset caches (for streaming writes). */ + i915_gem_chipset_flush(req->engine->i915); /* Unconditionally invalidate gpu caches and ensure that we do flush * any residual writes from the previous batch.