Commit e4c0d531 authored by Matt Roper's avatar Matt Roper
Browse files

drm/i915: Apply LUT validation checks to platforms more accurately (v3) 

Use of the new DRM_COLOR_LUT_NON_DECREASING test was a bit over-zealous;
it doesn't actually need to be applied to the degamma on "bdw-style"
platforms.  Likewise, we overlooked the fact that CHV should have that
test applied to the gamma LUT as well as the degamma LUT.

Rather than adding more complicated platform checking to
intel_color_check(), let's just store the appropriate set of LUT
validation flags for each platform in the intel_device_info structure.

v2:
 - Shuffle around LUT size tests so that the hardware-specific tests
   won't be applied to legacy gamma tables.  (Ville)
 - Add a debug message so that it will be easier to understand why an
   atomic transaction involving incorrectly-sized LUT's got rejected
   by the driver.

v3:
 - Switch size_t's to int's.  (Ville)

Fixes: 85e2d61e ("drm/i915: Validate userspace-provided color management LUT's (v4)")
References: https://lists.freedesktop.org/archives/intel-gfx/2019-January/187634.html


Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: default avatarMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190130181022.4291-1-matthew.d.roper@intel.com
parent c0550305

drivers/gpu/drm/i915/i915_pci.c

+8 −2
Original line number Diff line number Diff line
@@ -67,9 +67,15 @@ 
#define BDW_COLORS \

	.color = { .degamma_lut_size = 512, .gamma_lut_size = 512 }

#define CHV_COLORS \

	.color = { .degamma_lut_size = 65, .gamma_lut_size = 257 }

	.color = { .degamma_lut_size = 65, .gamma_lut_size = 257, \

		   .degamma_lut_tests = DRM_COLOR_LUT_NON_DECREASING, \

		   .gamma_lut_tests = DRM_COLOR_LUT_NON_DECREASING, \

	}

#define GLK_COLORS \

	.color = { .degamma_lut_size = 0, .gamma_lut_size = 1024 }

	.color = { .degamma_lut_size = 0, .gamma_lut_size = 1024, \

		   .degamma_lut_tests = DRM_COLOR_LUT_NON_DECREASING | \

					DRM_COLOR_LUT_EQUAL_CHANNELS, \

	}



/* Keep in gen based order, and chronological order within a gen */

drivers/gpu/drm/i915/intel_color.c

+30 −30
Original line number Diff line number Diff line
@@ -605,48 +605,48 @@ void intel_color_load_luts(struct intel_crtc_state *crtc_state) 
	dev_priv->display.load_luts(crtc_state);

}



static int check_lut_size(const struct drm_property_blob *lut, int expected)

{

	int len;



	if (!lut)

		return 0;



	len = drm_color_lut_size(lut);

	if (len != expected) {

		DRM_DEBUG_KMS("Invalid LUT size; got %d, expected %d\n",

			      len, expected);

		return -EINVAL;

	}



	return 0;

}



int intel_color_check(struct intel_crtc_state *crtc_state)

{

	struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev);

	size_t gamma_length, degamma_length;

	uint32_t tests = DRM_COLOR_LUT_NON_DECREASING;

	int gamma_length, degamma_length;

	u32 gamma_tests, degamma_tests;



	degamma_length = INTEL_INFO(dev_priv)->color.degamma_lut_size;

	gamma_length = INTEL_INFO(dev_priv)->color.gamma_lut_size;

	degamma_tests = INTEL_INFO(dev_priv)->color.degamma_lut_tests;

	gamma_tests = INTEL_INFO(dev_priv)->color.gamma_lut_tests;



	/*

	 * All of our platforms mandate that the degamma curve be

	 * non-decreasing.  Additionally, GLK and gen11 only accept a single

	 * value for red, green, and blue in the degamma table.  Make sure

	 * userspace didn't try to pass us something we can't handle.

	 *

	 * We don't have any extra hardware constraints on the gamma table,

	 * so no need to explicitly check it.

	 */

	if (IS_GEMINILAKE(dev_priv) || INTEL_GEN(dev_priv) >= 10)

		tests |= DRM_COLOR_LUT_EQUAL_CHANNELS;

	/* Always allow legacy gamma LUT with no further checking. */

	if (crtc_state_is_legacy_gamma(crtc_state))

		return 0;



	if (drm_color_lut_check(crtc_state->base.degamma_lut, tests) != 0)

	if (check_lut_size(crtc_state->base.degamma_lut, degamma_length) ||

	    check_lut_size(crtc_state->base.gamma_lut, gamma_length))

		return -EINVAL;



	/*

	 * We allow both degamma & gamma luts at the right size or

	 * NULL.

	 */

	if ((!crtc_state->base.degamma_lut ||

	     drm_color_lut_size(crtc_state->base.degamma_lut) == degamma_length) &&

	    (!crtc_state->base.gamma_lut ||

	     drm_color_lut_size(crtc_state->base.gamma_lut) == gamma_length))

		return 0;

	if (drm_color_lut_check(crtc_state->base.degamma_lut, degamma_tests) ||

	    drm_color_lut_check(crtc_state->base.gamma_lut, gamma_tests))

		return -EINVAL;



	/*

	 * We also allow no degamma lut/ctm and a gamma lut at the legacy

	 * size (256 entries).

	 */

	if (crtc_state_is_legacy_gamma(crtc_state))

		return 0;



	return -EINVAL;

	return 0;

}



void intel_color_init(struct intel_crtc *crtc)

drivers/gpu/drm/i915/intel_device_info.h

+2 −0
Original line number Diff line number Diff line
@@ -189,6 +189,8 @@ struct intel_device_info { 
	struct color_luts {

		u16 degamma_lut_size;

		u16 gamma_lut_size;

		u32 degamma_lut_tests;

		u32 gamma_lut_tests;

	} color;

};