Re: [Intel-gfx] [PATCH 2/2] drm/i915: Compare user's 64b GTT offset even on 32b

[Lionel Landwerlin <lionel.g.landwerlin@intel.com>]

Reminds me that we should probably update the uAPI...

struct drm_i915_gem_exec_object2 has a u64 flags and all the 
EXEC_OBJECT_* flags are (1<<X)

-
Lionel

On 25/10/2018 10:18, Chris Wilson wrote:
> Beware mixing unsigned long constants and 64b values, as on 32b the
> constant will be zero extended and discard the high 32b when used as
> a mask!
>
> Reported-by: Sergii Romantsov <sergii.romantsov@globallogic.com>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108282
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> Cc: stable@vger.kernel.org
> ---
>   drivers/gpu/drm/i915/gvt/gtt.h             | 1 -
>   drivers/gpu/drm/i915/i915_gem_execbuffer.c | 2 +-
>   drivers/gpu/drm/i915/i915_gem_gtt.h        | 2 ++
>   3 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.h b/drivers/gpu/drm/i915/gvt/gtt.h
> index 7a9b36176efb..bfb6f652b09f 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.h
> +++ b/drivers/gpu/drm/i915/gvt/gtt.h
> @@ -35,7 +35,6 @@
>   #define _GVT_GTT_H_
>   
>   #define I915_GTT_PAGE_SHIFT         12
> -#define I915_GTT_PAGE_MASK		(~(I915_GTT_PAGE_SIZE - 1))
>   
>   struct intel_vgpu_mm;
>   
> diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> index f90a09b83370..1a1c04db6c80 100644
> --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> @@ -460,7 +460,7 @@ eb_validate_vma(struct i915_execbuffer *eb,
>   	 * any non-page-aligned or non-canonical addresses.
>   	 */
>   	if (unlikely(entry->flags & EXEC_OBJECT_PINNED &&
> -		     entry->offset != gen8_canonical_addr(entry->offset & PAGE_MASK)))
> +		     entry->offset != gen8_canonical_addr(entry->offset & I915_GTT_PAGE_MASK)))
>   		return -EINVAL;
>   
>   	/* pad_to_size was once a reserved field, so sanitize it */
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
> index aa8307043036..5d2c5ba55ad8 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.h
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
> @@ -49,6 +49,8 @@
>   #define I915_GTT_PAGE_SIZE I915_GTT_PAGE_SIZE_4K
>   #define I915_GTT_MAX_PAGE_SIZE I915_GTT_PAGE_SIZE_2M
>   
> +#define I915_GTT_PAGE_MASK -I915_GTT_PAGE_SIZE
> +
>   #define I915_GTT_MIN_ALIGNMENT I915_GTT_PAGE_SIZE
>   
>   #define I915_FENCE_REG_NONE -1