[Intel-gfx] [PATCH i-g-t] i915/gem_softpin: Check the last 32b page is excluded

[Tang, CQ]

> -----Original Message-----
> From: Chris Wilson <chris at chris-wilson.co.uk>
> Sent: Wednesday, December 16, 2020 12:53 PM
> To: intel-gfx at lists.freedesktop.org
> Cc: Chris Wilson <chris at chris-wilson.co.uk>; Tang, CQ <cq.tang at intel.com>
> Subject: [PATCH i-g-t] i915/gem_softpin: Check the last 32b page is excluded
> 
> In order to prevent issues with 32b stateless address, the last page under 4G
> is excluded for non-48b objects.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: CQ Tang <cq.tang at intel.com>
> ---
>  tests/i915/gem_softpin.c | 37
> +++++++++++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
> 
> diff --git a/tests/i915/gem_softpin.c b/tests/i915/gem_softpin.c index
> a3e6dcac3..703beb77d 100644
> --- a/tests/i915/gem_softpin.c
> +++ b/tests/i915/gem_softpin.c
> @@ -156,6 +156,39 @@ static void test_zero(int i915)
>  	gem_close(i915, object.handle);
>  }
> 
> +static void test_32b_last_page(int i915) {
> +	uint64_t sz, gtt = gem_aperture_size(i915);
> +	struct drm_i915_gem_exec_object2 object = {
> +		.flags = EXEC_OBJECT_PINNED,
> +	};
> +	struct drm_i915_gem_execbuffer2 execbuf = {
> +		.buffers_ptr = to_user_pointer(&object),
> +		.buffer_count = 1,
> +	};
> +
> +	/*
> +	 * The last page under 32b is excluded for !48b objects in order to
> +	 * prevent issues with stateless addressing.
> +	 */
> +
> +	igt_require(gtt >= 1ull << 32);
> +	object.handle = batch_create(i915, &sz),

Where is this batch_create() version?

--CQ

> +
> +	object.offset = 1ull << 32;
> +	object.offset -= sz;
> +	igt_assert_f(__gem_execbuf(i915, &execbuf) == -EINVAL,
> +		     "execbuf succeeded with object.offset=%llx
> + %"PRIx64"\n",
> +		     object.offset, sz);
> +
> +	object.offset -= 4096;
> +	igt_assert_f(__gem_execbuf(i915, &execbuf) == 0,
> +		     "execbuf failed with object.offset=%llx + %"PRIx64"\n",
> +		     object.offset, sz);
> +
> +	gem_close(i915, object.handle);
> +}
> +
>  static void test_softpin(int fd)
>  {
>  	const uint32_t size = 1024 * 1024;
> @@ -622,6 +655,10 @@ igt_main
>  		igt_require(gem_uses_full_ppgtt(fd));
>  		test_zero(fd);
>  	}
> +	igt_subtest("32b-excludes-last-page") {
> +		igt_require(gem_uses_full_ppgtt(fd));
> +		test_32b_last_page(fd);
> +	}
>  	igt_subtest("softpin")
>  		test_softpin(fd);
>  	igt_subtest("overlap")
> --
> 2.29.2