vmaCreateBuffer() fails on Raspberry Pi with Mesa drivers when called with VMA_MEMORY_USAGE_AUTO and VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT.

[cos-public]

Call to vmaCreateBuffer() fails when called with VMA_MEMORY_USAGE_AUTO and VMA_ALLOCATION_CREATE_HOST_ACCESS_RANDOM_BIT as random host access requires VK_MEMORY_PROPERTY_HOST_CACHED_BIT. However, there is no memory type with such properties available on Raspberry Pi. Here is an excerpt from vulkaninfo:

==========
VULKANINFO
==========

Vulkan Instance Version: 1.3.250
...
Device Properties and Extensions:
=================================
GPU0:
VkPhysicalDeviceProperties:
---------------------------
	apiVersion        = 1.2.246 (4202742)
	driverVersion     = 23.1.3 (96473091)
	vendorID          = 0x14e4
	deviceID          = 0xbe485fd3
	deviceType        = PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU
	deviceName        = V3D 4.2
	pipelineCacheUUID = aeb6494b-3e65-2f07-0af0-8fa9e0b21377
...
VkPhysicalDeviceMemoryProperties:
=================================
memoryHeaps: count = 1
	memoryHeaps[0]:
		size   = 969521152 (0x39c9b800) (924.61 MiB)
		budget = 969521152 (0x39c9b800) (924.61 MiB)
		usage  = 0 (0x00000000) (0.00 B)
		flags: count = 1
			MEMORY_HEAP_DEVICE_LOCAL_BIT
memoryTypes: count = 1
	memoryTypes[0]:
		heapIndex     = 0
		propertyFlags = 0x0007: count = 3
			MEMORY_PROPERTY_DEVICE_LOCAL_BIT
			MEMORY_PROPERTY_HOST_VISIBLE_BIT
			MEMORY_PROPERTY_HOST_COHERENT_BIT
		usable for:
			IMAGE_TILING_OPTIMAL:
				color images
				FORMAT_D16_UNORM
				FORMAT_X8_D24_UNORM_PACK32
				FORMAT_D32_SFLOAT
				FORMAT_D24_UNORM_S8_UINT
				(non-sparse)
			IMAGE_TILING_LINEAR:
				color images
				(non-sparse)

I would expect that such a broad request would return something usable on any platform.
Is this the intended behaviour?

[adam-sawicki-a]

Thank you for reporting this problem. You are right - Vulkan specification doesn't guarantee that a memory type with HOST_CACHED flag exists, while VMA_MEMORY_USAGE_AUTO should work on any platform. It will be fixed ASAP.

[adam-sawicki-a]

I've pushed a fix. Please let me know if it works on your platform.

[cos-public]

Sorry for the delay. Just got back to the next iteration with the project. Yes, it's working as expected now. Thank you.

[adam-sawicki-a]

Thank you for confirmation. I assume I can close the ticket now.