[Intel-gfx] [PATCH i-g-t 4/4] gem_create: Convert stolen test to uABI checking

[Chris Wilson]

On Thu, Mar 30, 2017 at 05:58:09PM +0100, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
> Stolen never materialized so convert this test into checking
> that the garbage in padding remains legal.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> ---
>  tests/gem_create.c | 39 ++++++++++++---------------------------
>  1 file changed, 12 insertions(+), 27 deletions(-)
> 
> diff --git a/tests/gem_create.c b/tests/gem_create.c
> index 21df13f7b655..0dad06c784c5 100644
> --- a/tests/gem_create.c
> +++ b/tests/gem_create.c
> @@ -27,8 +27,7 @@
>  
>  /** @file gem_create.c
>   *
> - * This is a test for the extended and old gem_create ioctl, that
> - * includes allocation of object from stolen memory and shmem.
> + * This is a test for the gem_create ioctl.
>   *
>   * The goal is to simply ensure that basics work and invalid input
>   * combinations are rejected.
> @@ -62,36 +61,22 @@ IGT_TEST_DESCRIPTION("This is a test for the extended & old gem_create ioctl,"
>  		     " that includes allocation of object from stolen memory"
>  		     " and shmem.");
>  
> -#define CLEAR(s) memset(&s, 0, sizeof(s))
>  #define PAGE_SIZE 4096
>  
> -struct local_i915_gem_create_v2 {
> -	uint64_t size;
> -	uint32_t handle;
> -	uint32_t pad;
> -#define I915_CREATE_PLACEMENT_STOLEN (1<<0)
> -	uint32_t flags;
> -} create;
> -
> -#define LOCAL_IOCTL_I915_GEM_CREATE       DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GEM_CREATE, struct local_i915_gem_create_v2)
> -
> -static void invalid_flag_test(int fd)
> +/*
> + * Verify that historical omission of checking for garbage in the padding
> + * field still holds.
> + */
> +static void test_pad_garbage(int fd)
>  {
> +	struct drm_i915_gem_create create = { };
>  	int ret;
>  
> -	gem_require_stolen_support(fd);
> -
>  	create.handle = 0;
>  	create.size = PAGE_SIZE;
> -	create.flags = ~I915_CREATE_PLACEMENT_STOLEN;
> -	ret = drmIoctl(fd, LOCAL_IOCTL_I915_GEM_CREATE, &create);
> -
> -	igt_assert(ret <= 0);
> -
> -	create.flags = ~0;
> -	ret = drmIoctl(fd, LOCAL_IOCTL_I915_GEM_CREATE, &create);
> -
> -	igt_assert(ret <= 0);
> +	create.pad = 1;
> +	ret = drmIoctl(fd, DRM_IOCTL_I915_GEM_CREATE, &create);
> +	igt_assert_eq(ret, 0);
>  }
>  
>  static void invalid_size_test(int fd)
> @@ -134,8 +119,8 @@ igt_main
>  		fd = drm_open_driver(DRIVER_INTEL);
>  	}
>  
> -	igt_subtest("stolen-invalid-flag")
> -		invalid_flag_test(fd);
> +	igt_subtest("basic-pad-garbage")
> +		test_pad_garbage(fd);

Not basic though. I just dislike having negative tests that we intend to
break be part of basic. (I dislike negative tests in general as they are
restrictive and limit creativity, a false limitation in terms of ABI.)
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre