On 09/19/14 17:36, Daniel Vetter wrote:
> Hm, I don't see what this fixes, except maybe a race in the kernel?
> Testcase plus some analysis in the commit message about what blows up
> exactly and how this fixes it is required here.

Currently we can reproduce this issue using our "internal" projects in 
multi-threaded configurations.
I'll try to extend test [1] to reproduce issue. Without this patch 
DRM_IOCTL_I915_GEM_GET_TILING ioctl
returned -ENOENT from i915_gem_get_tiling function 
(drivers/gpu/drm/i915/i915_gem_tiling.c):

 /**
 * Returns the current tiling mode and required bit 6 swizzling for the object.
 */
int
i915_gem_get_tiling(struct drm_device *dev, void *data,
                   struct drm_file *file)
{
        struct drm_i915_gem_get_tiling *args = data;
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct drm_i915_gem_object *obj;

        obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
        if (&obj->base == NULL)
                return -ENOENT;


This ioctl is being called in libdrm in function 
drm_intel_bo_gem_create_from_prime:

        get_tiling.handle = bo_gem->gem_handle;
        ret = drmIoctl(bufmgr_gem->fd,
                       DRM_IOCTL_I915_GEM_GET_TILING,
                       &get_tiling);
        if (ret != 0) {
                drm_intel_gem_bo_unreference(&bo_gem->bo);
                return NULL;
        }

[1] http://lists.freedesktop.org/archives/intel-gfx/2014-September/052586.html

-- 
jacek
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to