On Thu, 01 Dec 2011 13:30:18 +0100, Jiri Slaby jslaby@suse.cz wrote:
Hi,
both yesterday and today, my GPU hung. Both happened when I opened google front page in firefox.
I'm running 3.2.0-rc3-next-20111130. Given it happened twice in the past 24 hours, it looks like a regression from next-20111124. Or is this a userspace issue (I might updated some packages)?
i915_error_state dumps from the two hangs are here: http://www.fi.muni.cz/~xslaby/sklad/panics/915_error_state_0 http://www.fi.muni.cz/~xslaby/sklad/panics/915_error_state_second
Both error states contain the same bug: a fence register in conflict with the command stream. The batch is using the buffer at 0x03d0000 as an untiled 40x40 rgba buffer with pitch 192. However, a fence register is programmed to fence[3] = 03d00001 valid, x-tiled, pitch: 512, start: 0x03d00000, size: 1048576
Also note that buffer is also not listed as currently active, so presumably we reused the buffer as tiled (and so reprogrammed the fence registered) before the GPU retired the batch. That sounds eerily similar to this bug:
From 2b76187d2f5fc2352e391914b1828f91f93bb356 Mon Sep 17 00:00:00 2001
From: Chris Wilson chris@chris-wilson.co.uk Date: Tue, 29 Nov 2011 15:12:16 +0000 Subject: [PATCH] drm/i915: Only clear the GPU domains upon a successful finish
By clearing the GPU read domains before waiting upon the buffer, we run the risk of the wait being interrupted and the domains prematurely cleared. The next time we attempt to wait upon the buffer (after userspace handles the signal), we believe that the buffer is idle and so skip the wait.
There are a number of bugs across all generations which show signs of an overly haste reuse of active buffers.
Such as:
https://bugs.freedesktop.org/show_bug.cgi?id=29046 https://bugs.freedesktop.org/show_bug.cgi?id=35863 https://bugs.freedesktop.org/show_bug.cgi?id=38952 https://bugs.freedesktop.org/show_bug.cgi?id=40282 https://bugs.freedesktop.org/show_bug.cgi?id=41098 https://bugs.freedesktop.org/show_bug.cgi?id=41102 https://bugs.freedesktop.org/show_bug.cgi?id=41284 https://bugs.freedesktop.org/show_bug.cgi?id=42141
A couple of those pre-date i915_gem_object_finish_gpu(), so may be unrelated (such as a wild write from a userspace command buffer), but this does look like a convincing cause for most of those bugs.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: stable@kernel.org Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch Reviewed-by: Eugeni Dodonov eugeni.dodonov@intel.com --- drivers/gpu/drm/i915/i915_gem.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index d560175..036bc58 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -3087,10 +3087,13 @@ i915_gem_object_finish_gpu(struct drm_i915_gem_object *obj) return ret; }
+ ret = i915_gem_object_wait_rendering(obj); + if (ret) + return ret; + /* Ensure that we invalidate the GPU's caches and TLBs. */ obj->base.read_domains &= ~I915_GEM_GPU_DOMAINS; - - return i915_gem_object_wait_rendering(obj); + return 0; }
/**