diff --git a/src/nbl/video/CVulkanLogicalDevice.cpp b/src/nbl/video/CVulkanLogicalDevice.cpp
index ff5febb4b1..847885da02 100644
--- a/src/nbl/video/CVulkanLogicalDevice.cpp
+++ b/src/nbl/video/CVulkanLogicalDevice.cpp
@@ -635,12 +635,15 @@ core::smart_refctd_ptr<IDescriptorPool> CVulkanLogicalDevice::createDescriptorPo
     return nullptr;
 }
 
+// a lot of empirical research went into defining this constant
+constexpr uint32_t MaxDescriptorSetAsWrites = 69u;
+
 void CVulkanLogicalDevice::updateDescriptorSets_impl(const SUpdateDescriptorSetsParams& params)
 {
     // Each pNext member of any structure (including this one) in the pNext chain must be either NULL or a pointer to a valid instance of
     // VkWriteDescriptorSetAccelerationStructureKHR, VkWriteDescriptorSetAccelerationStructureNV, or VkWriteDescriptorSetInlineUniformBlockEXT
     core::vector<VkWriteDescriptorSet> vk_writeDescriptorSets(params.writes.size(),{VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,nullptr});
-    core::vector<VkWriteDescriptorSetAccelerationStructureKHR> vk_writeDescriptorSetAS(69u,{VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET_ACCELERATION_STRUCTURE_KHR,nullptr});
+    core::vector<VkWriteDescriptorSetAccelerationStructureKHR> vk_writeDescriptorSetAS(MaxDescriptorSetAsWrites,{VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET_ACCELERATION_STRUCTURE_KHR,nullptr});
 
     core::vector<VkDescriptorBufferInfo> vk_bufferInfos(params.bufferCount);
     core::vector<VkDescriptorImageInfo> vk_imageInfos(params.imageCount);
@@ -735,7 +738,7 @@ void CVulkanLogicalDevice::nullifyDescriptors_impl(const std::span<const IGPUDes
     }
 
 	core::vector<VkWriteDescriptorSet> vk_writeDescriptorSets(drops.size(),{VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,nullptr});
-	core::vector<VkWriteDescriptorSetAccelerationStructureKHR> vk_writeDescriptorSetAS(69u,{VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET_ACCELERATION_STRUCTURE_KHR,nullptr});
+	core::vector<VkWriteDescriptorSetAccelerationStructureKHR> vk_writeDescriptorSetAS(MaxDescriptorSetAsWrites,{VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET_ACCELERATION_STRUCTURE_KHR,nullptr});
 
 	size_t maxSize = 0;
 	for (auto i = 0; i < drops.size(); i++)
@@ -791,6 +794,7 @@ void CVulkanLogicalDevice::nullifyDescriptors_impl(const std::span<const IGPUDes
 			case asset::IDescriptor::EC_ACCELERATION_STRUCTURE:
 				outWriteAS->accelerationStructureCount = write.count;
 				outWriteAS->pAccelerationStructures = reinterpret_cast<VkAccelerationStructureKHR*>(nullDescriptors.data());
+				outWrite->pNext = outWriteAS++;
 				break;
             default:
                 assert(!"Invalid code path.");
diff --git a/src/nbl/video/ILogicalDevice.cpp b/src/nbl/video/ILogicalDevice.cpp
index 3f00a80cfb..2c852c7631 100644
--- a/src/nbl/video/ILogicalDevice.cpp
+++ b/src/nbl/video/ILogicalDevice.cpp
@@ -451,6 +451,9 @@ bool ILogicalDevice::nullifyDescriptors(const std::span<const IGPUDescriptorSet:
         auto ds = drop.dstSet;
         if (!ds || !ds->wasCreatedBy(this))
             return false;
+        // (no binding)
+        if (ds->getBindingType(drop.binding) == asset::IDescriptor::E_TYPE::ET_COUNT)
+            return false;
     }
 
     for (const auto& drop : dropDescriptors)