From d472fcc8379c062bd56a3876fc6ef22258f14a91 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Mon, 24 Nov 2014 11:12:42 +0100 Subject: [PATCH] drm/i915: Disallow pin ioctl completely for kms drivers The problem here is that SNA pins batchbuffers to etch out a bit more performance. Iirc it started out as a w/a for i830M (which we've implemented in the kernel since a long time already). The problem is that the pin ioctl wasn't added in commit d23db88c3ab233daed18709e3a24d6c95344117f Author: Chris Wilson Date: Fri May 23 08:48:08 2014 +0200 drm/i915: Prevent negative relocation deltas from wrapping Fix this by simply disallowing pinning from userspace so that the kernel is in full control of batch placement again. Especially since distros are moving towards running X as non-root, so most users won't even be able to see any benefits. UMS support is dead now, but we need this minimal patch for backporting. Follow-up patch will remove the pin ioctl code completely. Note to backporters: You must have both commit b45305fce5bb1abec263fcff9d81ebecd6306ede Author: Daniel Vetter Date: Mon Dec 17 16:21:27 2012 +0100 drm/i915: Implement workaround for broken CS tlb on i830/845 which laned in 3.8 and commit c4d69da167fa967749aeb70bc0e94a457e5d00c1 Author: Chris Wilson Date: Mon Sep 8 14:25:41 2014 +0100 drm/i915: Evict CS TLBs between batches which is also marked cc: stable. Otherwise this could introduce a regression by disabling the userspace w/a without the kernel w/a being fully functional on i830/45. References: https://bugs.freedesktop.org/show_bug.cgi?id=76554#c116 Cc: stable@vger.kernel.org # requires c4d69da167fa967749a and v3.8 Cc: Chris Wilson Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_gem.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index fd17ccabd8a4..97b86a55e138 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4263,7 +4263,7 @@ i915_gem_pin_ioctl(struct drm_device *dev, void *data, struct drm_i915_gem_object *obj; int ret; - if (INTEL_INFO(dev)->gen >= 6) + if (drm_core_check_feature(dev, DRIVER_MODESET)) return -ENODEV; ret = i915_mutex_lock_interruptible(dev); @@ -4319,6 +4319,9 @@ i915_gem_unpin_ioctl(struct drm_device *dev, void *data, struct drm_i915_gem_object *obj; int ret; + if (drm_core_check_feature(dev, DRIVER_MODESET)) + return -ENODEV; + ret = i915_mutex_lock_interruptible(dev); if (ret) return ret;