I compiled Deno from source using the latest commit (fe884c5 as of writing).

I found that the following program causes Deno to hang on Linux (Ubuntu 22.04) and not finish execution (or at least not finish execution within 30 mins on my machine):

async function main() {
	const adapter = await navigator.gpu.requestAdapter();
	const device = await adapter.requestDevice();
	const buffer = device.createBuffer({
		mappedAtCreation: true,
		size: 12,
		usage: GPUBufferUsage.COPY_SRC
	});
	device.destroy();
}
main().catch(console.error);

On macOS, there is some different behavior. The following is output to the console:

No active command buffers for fence value 1
Failed to wait for buffer Id(0,1,mtl): Parent device is lost

It seems to be because mappedAtCreation is true. When mappedAtCreation is false, the program finishes executing on both macOS and Linux successfully.