diff --git a/spec/index.bs b/spec/index.bs
index 1abdac2585..26d529bf48 100644
--- a/spec/index.bs
+++ b/spec/index.bs
@@ -1950,6 +1950,9 @@ dictionary GPUBindGroupLayoutEntry {
     // Used for uniform buffer and storage buffer bindings.
     boolean hasDynamicOffset = false;
 
+    // Used for uniform buffer and storage buffer bindings.
+    GPUSize64 minBufferBindingSize = 0;
+
     // Used for sampled texture and storage texture bindings.
     GPUTextureViewDimension viewDimension;
 
@@ -1962,6 +1965,8 @@ dictionary GPUBindGroupLayoutEntry {
 };
 </script>
 
+Issue(https://github.com/gpuweb/gpuweb/issues/851): consider making `textureComponentType` and `storageTextureFormat` truly optional.
+
 <dl dfn-type=dict-member dfn-for=GPUBindGroupLayoutEntry>
     : <dfn>binding</dfn>
     ::
@@ -2105,8 +2110,8 @@ A {{GPUBindGroupLayout}} object has the following internal slots:
             {{GPUBindingType/"storage-buffer"}}, or
             {{GPUBindingType/"readonly-storage-buffer"}},
             ensure
-            |bindingDescriptor|.{{GPUBindGroupLayoutEntry/hasDynamicOffset}}
-            is `false`.
+            |bindingDescriptor|.{{GPUBindGroupLayoutEntry/hasDynamicOffset}} is `false`,
+            and |bindingDescriptor|.{{GPUBindGroupLayoutEntry/minBufferBindingSize}} is zero.
         1. If |bindingDescriptor|.{{GPUBindGroupLayoutEntry/type}} is **not**
             {{GPUBindingType/"sampled-texture"}},
             {{GPUBindingType/"readonly-storage-texture"}}, or
@@ -2188,24 +2193,7 @@ A {{GPUBindGroupLayout}} object has the following internal slots:
 Two {{GPUBindGroupLayout}} objects |a| and |b| are considered <dfn dfn>group-equivalent</dfn>
 if and only if, for any binding number |binding|, one of the following is true:
     - it's missing from both |a|.{{GPUBindGroupLayout/[[entryMap]]}} and |b|.{{GPUBindGroupLayout/[[entryMap]]}}.
-    - |a|.{{GPUBindGroupLayout/[[entryMap]]}}[|binding|] is [=entry-equivalent=] to |b|.{{GPUBindGroupLayout/[[entryMap]]}}[|binding|]
-</div>
-
-<div algorithm>
-Two {{GPUBindGroupLayoutEntry}} entries |a| and |b| are considered <dfn dfn>entry-equivalent</dfn> if all of the conditions are true:
-
-    1. |a|.{{GPUBindGroupLayoutEntry/binding}} == |b|.{{GPUBindGroupLayoutEntry/binding}}
-    1. |a|.{{GPUBindGroupLayoutEntry/visibility}} == |b|.{{GPUBindGroupLayoutEntry/visibility}}
-    1. |a|.{{GPUBindGroupLayoutEntry/type}} == |b|.{{GPUBindGroupLayoutEntry/type}}
-    1. if |a|.{{GPUBindGroupLayoutEntry/type}} is {{GPUBindingType/"uniform-buffer"}}, {{GPUBindingType/"storage-buffer"}}, or {{GPUBindingType/"readonly-storage-buffer"}}, then:
-        - |a|.{{GPUBindGroupLayoutEntry/hasDynamicOffset}} == |b|.{{GPUBindGroupLayoutEntry/hasDynamicOffset}}
-    1. if |a|.{{GPUBindGroupLayoutEntry/type}} is {{GPUBindingType/"sampled-texture"}}, then:
-        - |a|.{{GPUBindGroupLayoutEntry/viewDimension}} == |b|.{{GPUBindGroupLayoutEntry/viewDimension}}
-        - |a|.{{GPUBindGroupLayoutEntry/textureComponentType}} == |b|.{{GPUBindGroupLayoutEntry/textureComponentType}}
-        - |a|.{{GPUBindGroupLayoutEntry/multisampled}} == |b|.{{GPUBindGroupLayoutEntry/multisampled}}
-    1. if |a|.{{GPUBindGroupLayoutEntry/type}} is {{GPUBindingType/"readonly-storage-texture"}} or {{GPUBindingType/"writeonly-storage-texture"}}, then:
-        - |a|.{{GPUBindGroupLayoutEntry/viewDimension}} == |b|.{{GPUBindGroupLayoutEntry/viewDimension}}
-        - |a|.{{GPUBindGroupLayoutEntry/storageTextureFormat}} == |b|.{{GPUBindGroupLayoutEntry/storageTextureFormat}}
+    - |a|.{{GPUBindGroupLayout/[[entryMap]]}}[|binding|] == |b|.{{GPUBindGroupLayout/[[entryMap]]}}[|binding|]
 </div>
 
 If bind groups layouts are [=group-equivalent=] they can be interchangeably used in all contents.
@@ -2379,9 +2367,14 @@ A {{GPUBindGroup}} object has the following internal slots:
                 with {{GPUBufferUsage/STORAGE}} flag.
             1. The bound part designated by |bufferBinding|.{{GPUBufferBinding/offset}} and
                 |bufferBinding|.{{GPUBufferBinding/size}} must reside inside the buffer.
+            1. The effective binding size, that is either explict in |bufferBinding|.{{GPUBufferBinding/size}}
+                or derived from |bufferBinding|.{{GPUBufferBinding/offset}} and the full size of the buffer,
+                is greater than or equal to |layoutBinding|.{{GPUBindGroupLayoutEntry/minBufferBindingSize|GPUBindGroupLayoutEntry.minBufferBindingSize}}.
     </div>
 </div>
 
+Issue: define the "effective buffer binding size" separately.
+
 ## GPUPipelineLayout ## {#pipeline-layout}
 
 A {{GPUPipelineLayout}} defines the mapping between resources of all {{GPUBindGroup}} objects set up during command encoding in {{GPUProgrammablePassEncoder/setBindGroup(index, bindGroup, dynamicOffsets)|setBindGroup}}, and the shaders of the pipeline set by {{GPURenderEncoderBase/setPipeline(pipeline)|GPURenderEncoderBase.setPipeline}} or {{GPUComputePassEncoder/setPipeline(pipeline)|GPUComputePassEncoder.setPipeline}}.
@@ -2757,6 +2750,13 @@ A {{GPUProgrammableStageDescriptor}} describes the entry point in the user-provi
             the |binding| has to be a read-only storage buffer.
         1. If |entry|.{{GPUBindGroupLayoutEntry/type}} is {{GPUBindingType/"sampled-texture"}}, {{GPUBindingType/"readonly-storage-texture"}}, or {{GPUBindingType/"writeonly-storage-texture"}},
             the shader view dimension of the texture has to match |entry|.{{GPUBindGroupLayoutEntry/viewDimension}}.
+        1. If |entry|.{{GPUBindGroupLayoutEntry/minBufferBindingSize}} is not zero:
+              - If the last field of the corresponding structure defined in the shader has an unbounded array type,
+                then the value of |entry|.{{GPUBindGroupLayoutEntry/minBufferBindingSize}} must be greater than or equal to the
+                byte offset of that field plus the stride of the unbounded array.
+              - If the corresponding shader structure doesn't end with an unbounded array type,
+                then the value of |entry|.{{GPUBindGroupLayoutEntry/minBufferBindingSize}} must be greater than or equal to the
+                size of the structure.
 </div>
 
 Issue: is there a match/switch statement in bikeshed?