Test case provokes Vulkan validation error

[jimblandy]

I added the following test to wgpu/tests, and it provokes the complaints at bottom from the Vulkan validation layer:

//! Tests for texture copy bounds checks.

use std::num::NonZeroU32;
use crate::common::{initialize_test, TestParameters};

#[test]
fn bad_copy_origin() {
    fn try_origin(origin: wgpu::Origin3d, should_panic: bool) {
        let mut parameters = TestParameters::default();
        if should_panic {
            parameters = parameters.failure();
        }
           
        initialize_test(parameters, |ctx| {
            let texture = ctx.device.create_texture(&TEXTURE_DESCRIPTOR);
            let data = vec![255; BUFFER_SIZE as usize];
            ctx.queue.write_texture(
                wgpu::ImageCopyTexture {
                    texture: &texture,
                    mip_level: 0,
                    origin,
                    aspect: wgpu::TextureAspect::All,
                },
                &data,
                BUFFER_COPY_LAYOUT,
                TEXTURE_SIZE,
            );
        });
    }

    try_origin(wgpu::Origin3d { x: 0, y: 0, z: 0 }, false);
    try_origin(wgpu::Origin3d { x: 1, y: 0, z: 0 }, true);
    try_origin(wgpu::Origin3d { x: 0, y: 1, z: 0 }, true);
    try_origin(wgpu::Origin3d { x: 0, y: 0, z: 1 }, true);
}

const TEXTURE_SIZE: wgpu::Extent3d = wgpu::Extent3d {
    width: 64,
    height: 64,
    depth_or_array_layers: 1,
};

const TEXTURE_DESCRIPTOR: wgpu::TextureDescriptor = wgpu::TextureDescriptor {
    label: Some("CopyOrigin"),
    size: TEXTURE_SIZE,
    mip_level_count: 1,
    sample_count: 1,
    dimension: wgpu::TextureDimension::D2,
    format: wgpu::TextureFormat::Rgba8UnormSrgb,
    usage: wgpu::TextureUsages::COPY_DST.union(wgpu::TextureUsages::COPY_SRC),
};

const BYTES_PER_PIXEL: u32 = 4;

const BUFFER_SIZE: u32 = TEXTURE_SIZE.width * TEXTURE_SIZE.height * BYTES_PER_PIXEL;

const BUFFER_COPY_LAYOUT: wgpu::ImageDataLayout = wgpu::ImageDataLayout {
    offset: 0,
    bytes_per_row: NonZeroU32::new(TEXTURE_SIZE.width * BYTES_PER_PIXEL),
    rows_per_image: None,
};

Here's the validation error:

[2022-08-12T16:06:19Z ERROR wgpu_hal::vulkan::instance] VALIDATION [VUID-vkDestroyDevice-device-00378 (0x71500fba)]
    	Validation Error: [ VUID-vkDestroyDevice-device-00378 ] Object 0: handle = 0x7fa69c0d3d50, type = VK_OBJECT_TYPE_DEVICE; Object 1: handle = 0x49f000000049f, name = (wgpu internal) Staging, type = VK_OBJECT_TYPE_BUFFER; | MessageID = 0x71500fba | OBJ ERROR : For VkDevice 0x7fa69c0d3d50[], VkBuffer 0x49f000000049f[(wgpu internal) Staging] has not been destroyed. The Vulkan spec states: All child objects created on device must have been destroyed prior to destroying device (https://www.khronos.org/registry/vulkan/specs/1.3-extensions/html/vkspec.html#VUID-vkDestroyDevice-device-00378)
[2022-08-12T16:06:19Z ERROR wgpu_hal::vulkan::instance] 	objects: (type: DEVICE, hndl: 0x7fa69c0d3d50, name: ?), (type: BUFFER, hndl: 0x49f000000049f, name: (wgpu internal) Staging)
[2022-08-12T16:06:19Z ERROR wgpu_hal::vulkan::instance] VALIDATION [VUID-vkDestroyDevice-device-00378 (0x71500fba)]
    	Validation Error: [ VUID-vkDestroyDevice-device-00378 ] Object 0: handle = 0x7fa69c717250, type = VK_OBJECT_TYPE_DEVICE; Object 1: handle = 0x90000000009, name = (wgpu internal) Staging, type = VK_OBJECT_TYPE_BUFFER; | MessageID = 0x71500fba | OBJ ERROR : For VkDevice 0x7fa69c717250[], VkBuffer 0x90000000009[(wgpu internal) Staging] has not been destroyed. The Vulkan spec states: All child objects created on device must have been destroyed prior to destroying device (https://www.khronos.org/registry/vulkan/specs/1.3-extensions/html/vkspec.html#VUID-vkDestroyDevice-device-00378)
[2022-08-12T16:06:19Z ERROR wgpu_hal::vulkan::instance] 	objects: (type: DEVICE, hndl: 0x7fa69c717250, name: ?), (type: BUFFER, hndl: 0x90000000009, name: (wgpu internal) Staging)
[2022-08-12T16:06:19Z ERROR wgpu_hal::vulkan::instance] VALIDATION [VUID-vkDestroyDevice-device-00378 (0x71500fba)]
    	Validation Error: [ VUID-vkDestroyDevice-device-00378 ] Object 0: handle = 0x7fa69c5a2e30, type = VK_OBJECT_TYPE_DEVICE; Object 1: handle = 0x90000000009, name = (wgpu internal) Staging, type = VK_OBJECT_TYPE_BUFFER; | MessageID = 0x71500fba | OBJ ERROR : For VkDevice 0x7fa69c5a2e30[], VkBuffer 0x90000000009[(wgpu internal) Staging] has not been destroyed. The Vulkan spec states: All child objects created on device must have been destroyed prior to destroying device (https://www.khronos.org/registry/vulkan/specs/1.3-extensions/html/vkspec.html#VUID-vkDestroyDevice-device-00378)
[2022-08-12T16:06:19Z ERROR wgpu_hal::vulkan::instance] 	objects: (type: DEVICE, hndl: 0x7fa69c5a2e30, name: ?), (type: BUFFER, hndl: 0x90000000009, name: (wgpu internal) Staging)

[jimblandy]

Here's the language from the Vulkan spec (it's included in the validation output, but scrolled off to the side)

VUID-vkDestroyDevice-device-00378
All child objects created on device must have been destroyed prior to destroying device

[jimblandy]

I'm going to bet this has something to do with the test being expected to panic. It is supposed to reach the handle_error_fatal call in backend::direct::Context::queue_write_texture.

[jimblandy]

It seems like Global::queue_write_texture creates a staging buffer, but if an error occurs, it won't free it.
This upsets Vulkan validation.

Obviously, there should be some sort of Drop involved somewhere. But properly freeing the buffer entails having a &mut Device, and that's going to be "hard" to obtain in a drop implementation.