Validate DownlevelFlags::READ_ONLY_DEPTH_STENCIL (#4031)

CHANGELOG.md

@@ -67,6 +67,7 @@ By @Valaphee in [#3402](https://github.com/gfx-rs/wgpu/pull/3402)
 ### Changes
 
 - Omit texture store bound checks since they are no-ops if out of bounds on all APIs. By @teoxoy in [#3975](https://github.com/gfx-rs/wgpu/pull/3975)
+- Validate `DownlevelFlags::READ_ONLY_DEPTH_STENCIL`. By @teoxoy in [#4031](https://github.com/gfx-rs/wgpu/pull/4031)
 
 ### Bug Fixes
 

wgpu-core/src/command/render.rs

@@ -960,7 +960,13 @@ impl<'a, A: HalApi> RenderPassInfo<'a, A> {
 
             (is_depth_read_only, is_stencil_read_only) = at.depth_stencil_read_only(ds_aspects)?;
 
-            let usage = if is_depth_read_only && is_stencil_read_only {
+            let usage = if is_depth_read_only
+                && is_stencil_read_only
+                && device
+                    .downlevel
+                    .flags
+                    .contains(wgt::DownlevelFlags::READ_ONLY_DEPTH_STENCIL)
+            {
                 hal::TextureUses::DEPTH_STENCIL_READ | hal::TextureUses::RESOURCE
             } else {
                 hal::TextureUses::DEPTH_STENCIL_WRITE

wgpu-types/src/lib.rs

@@ -1269,8 +1269,8 @@ bitflags::bitflags! {
         const INDIRECT_EXECUTION = 1 << 2;
         /// Supports non-zero `base_vertex` parameter to indexed draw calls.
         const BASE_VERTEX = 1 << 3;
-        /// Supports reading from a depth/stencil buffer while using as a read-only depth/stencil
-        /// attachment.
+        /// Supports reading from a depth/stencil texture while using it as a read-only
+        /// depth/stencil attachment.
         ///
         /// The WebGL2 and GLES backends do not support RODS.
         const READ_ONLY_DEPTH_STENCIL = 1 << 4;