MoltenVK broke between 1.3 and 1.4 for my app on iPad 8th gen

[hrydgard]

The latest version on MoltenVK works great with my app on iPhone 12 Pro, but on iPad 8th gen, it's completely busted: My app does start up but bilinear filtering doesn't work (!) and as soon as it does anything complicated, it crashes:

IOGPUMetalError: Caused GPU Address Fault Error (0000000b:kIOGPUCommandBufferCallbackErrorPageFault)
Execution of the command buffer was aborted due to an error during execution. Caused GPU Address Fault Error (0000000b:kIOGPUCommandBufferCallbackErrorPageFault)

[mvk-error] VK_ERROR_OUT_OF_DEVICE_MEMORY: Lost VkDevice after MTLCommandBuffer "mainCmd0" execution failed 

(code 3): Caused GPU Address Fault Error (0000000b:kIOGPUCommandBufferCallbackErrorPageFault)

39:40:517 audiot0      E[G3D]: Vulkan/VulkanDebug.cpp:165 VKDEBUG: ERROR(validation:0) 

VK_ERROR_OUT_OF_DEVICE_MEMORY: Lost VkDevice after MTLCommandBuffer "mainCmd0" execution failed (code 3): Caused GPU Address Fault Error (0000000b:kIOGPUCommandBufferCallbackErrorPageFault)

39:40:517 audiot0      E[SYSTEM]: Common/Log.cpp:116 
39:40:518 audiot0      I[SYSTEM]: Log/LogManager.cpp:380 Device lost in vkWaitForFence

Note that this vulkan code passes all validation on other platforms, and as already mentioned, works fine on Mac and on iPhone 12. It's just broken on 8th gen iPads. So I'll have to stick with 1.3 for now.

Is this some known issue, or should I make the effort to bisect MoltenVK between 1.3 and 1.4? (I'm happy to do so if this is unknonw).