Semaphores still cause problems on some machines: > From Udo Steinberg: > > With Linux-3.2-rc6 I'm frequently seeing GPU hangs when large amounts of > text scroll in an xterm, such as when extracting a tar archive. Such as this > one (note the timestamps): > > I can reproduce it fairly easily with something > as simple as: > > while true; do dmesg; done This patch turns them off on SNB while leaving them on for IVB. Reported-by: Udo Steinberg <udo at hypervisor.org> Cc: Daniel Vetter <daniel at ffwll.ch> Cc: Eugeni Dodonov <eugeni at dodonov.net> Signed-off-by: Keith Packard <keithp at keithp.com> --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index c681dc1..b9da890 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -756,9 +756,9 @@ intel_enable_semaphores(struct drm_device *dev) if (i915_semaphores >= 0) return i915_semaphores; - /* Enable semaphores on SNB when IO remapping is off */ + /* Disable semaphores on SNB */ if (INTEL_INFO(dev)->gen == 6) - return !intel_iommu_enabled; + return 0; return 1; } -- 1.7.7.3