From: Maíra Canal Date: Wed, 12 Apr 2023 14:29:23 +0000 (-0300) Subject: drm/gem: Check for valid formats X-Git-Tag: v6.6.17~3937^2~23^2~441 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;ds=sidebyside;h=c91acda3a380bcaf41b67c8fbab668ef8ddf91c3;p=platform%2Fkernel%2Flinux-rpi.git drm/gem: Check for valid formats Currently, drm_gem_fb_create() doesn't check if the pixel format is supported, which can lead to the acceptance of invalid pixel formats e.g. the acceptance of invalid modifiers. Therefore, add a check for valid formats on drm_gem_fb_create(). Note that this check is only valid for atomic drivers, because, for non-atomic drivers, checking drm_any_plane_has_format() is not possible since the format list for the primary plane is fake, and we'd therefore reject valid formats. Adding this check to drm_gem_fb_create() will guarantee that the igt@kms_addfb_basic@addfb25-bad-modifier IGT test passes for drivers using this callback. This commit is a recapture of a series sent a while ago. Initially, I sent a patch [1] similar to this one in which I introduced the format check to drm_gem_fb_create(). Based on the feedback on the patch, I placed the check inside framebuffer_check() [2] so that it wouldn't be needed to hit any driver-specific code path when the check fails. Therefore, we could remove the check from the specific drivers (i915, amdgpu, and vmwgfx). But, with some new feedback, it was shown that introducing this check inside framebuffer_check() is problematic for the i915 driver [3]. For the i915 driver, in the legacy case, in which we don't get the modifier from the userspace, i915's fb_create hook computes the right modifier, which isn't necessarily linear. Therefore, if we check the modifier before that point, we might get wrong answers. So, I kept the check inside the i915 driver and removed the check from amdgpu and vmwgfx [4]. But, this yet hasn't solved the i915 problem [5]. As we cannot add the check inside framebuffer_check() without affecting the i915 behavior, this commit went back to the original patch. This way we can guarantee a more uniform behavior from the drivers that use the drm_gem_fb_create() callback. [1] https://lore.kernel.org/dri-devel/20230103125322.855089-1-mcanal@igalia.com/T/ [2] https://lore.kernel.org/dri-devel/20230109105807.18172-1-mcanal@igalia.com/T/ [3] https://lore.kernel.org/dri-devel/Y8AAdW2y7zN7DCUZ@intel.com/ [4] https://lore.kernel.org/dri-devel/20230113112743.188486-1-mcanal@igalia.com/T/ [5] https://lore.kernel.org/dri-devel/Y8FXWvEhO7GCRKVJ@intel.com/ Signed-off-by: Maíra Canal Reviewed-by: Ville Syrjälä Acked-by: Daniel Vetter Signed-off-by: Maíra Canal Link: https://patchwork.freedesktop.org/patch/msgid/20230412142923.136707-1-mcanal@igalia.com --- diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 1f8a5eb..68bdafa 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -276,11 +276,8 @@ Various hold-ups: - Need to switch to drm_fbdev_generic_setup(), otherwise a lot of the custom fb setup code can't be deleted. -- Many drivers wrap drm_gem_fb_create() only to check for valid formats. For - atomic drivers we could check for valid formats by calling - drm_plane_check_pixel_format() against all planes, and pass if any plane - supports the format. For non-atomic that's not possible since like the format - list for the primary plane is fake and we'd therefor reject valid formats. +- Need to switch to drm_gem_fb_create(), as now drm_gem_fb_create() checks for + valid formats for atomic drivers. - Many drivers subclass drm_framebuffer, we'd need a embedding compatible version of the varios drm_gem_fb_create functions. Maybe called diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c index e93533b..b8a615a 100644 --- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c +++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c @@ -9,6 +9,7 @@ #include #include +#include #include #include #include @@ -164,6 +165,14 @@ int drm_gem_fb_init_with_funcs(struct drm_device *dev, return -EINVAL; } + if (drm_drv_uses_atomic_modeset(dev) && + !drm_any_plane_has_format(dev, mode_cmd->pixel_format, + mode_cmd->modifier[0])) { + drm_dbg(dev, "Unsupported pixel format %p4cc / modifier 0x%llx\n", + &mode_cmd->pixel_format, mode_cmd->modifier[0]); + return -EINVAL; + } + for (i = 0; i < info->num_planes; i++) { unsigned int width = mode_cmd->width / (i ? info->hsub : 1); unsigned int height = mode_cmd->height / (i ? info->vsub : 1);