Opening a game, closing it, and opening another crashed or device-lost on
the Vulkan backend with VR enabled. D3D11 and D3D12 both restart cleanly,
so this was Vulkan-specific rather than an OpenXR runtime limitation.
Root cause, proven with VK_EXT_device_fault plus
VK_EXT_device_address_binding_report: the fault is a write-invalid at a
page-aligned address that the binding tracer reports as not owned by the
second game device. The OpenXR compositor still references resources that
lived on the first game VkDevice; destroying that device frees the memory
and the compositor later writes into the freed page. The D3D backends are
immune because their shared compositor resources are COM ref-counted,
while vkDestroyDevice frees unconditionally.
Fix: persist and reuse the VulkanContext (VkInstance and VkDevice) across
VR games, so vkCreateDevice/vkDestroyDevice run once per process and those
pages are never unmapped. Per-game objects are still fully recreated,
including the surface, swapchain, object cache, command buffers, and the
OpenXR session and XrInstance. A device-lost context is never persisted. A
non-VR launch, or a runtime requiring a device extension the persisted
device lacks, discards it and initializes fresh.
Two problems that persisting exposed:
- InitBackendInfo() creates and destroys a temporary VkInstance on every
game boot and then calls UnloadVulkanLibrary(), which nulls every global
Vulkan function pointer. Reuse now re-resolves the instance and device
dispatch for the persisted handles.
- That same UnloadVulkanLibrary() unmaps vulkan-1.dll on runtimes that do
not otherwise pin it, invalidating the persisted handles. This is why
VDXR still failed after SteamVR worked. Added KeepVulkanLibraryLoaded()
so unloading is suppressed while a device is persisted.
Also removes the XR_KHR_vulkan_enable2 path. Creating a second device
against a retained XrInstance crashes inside the runtime in a way SEH
cannot catch. The backend now always uses legacy XR_KHR_vulkan_enable,
where Dolphin owns instance and device creation and the runtime binds at
xrCreateSession.
Supporting changes: ordered OpenXR session teardown (ShutdownSession and
DestroySession), a device-lost guard in CommandBufferManager that stops
emulation instead of resubmitting to a dead device, synchronous release of
Dolphin views and framebuffers before xrDestroySwapchain, and the two GPU
fault diagnostics. Note that vkGetDeviceFaultInfoEXT must be called with
vendorBinarySize zeroed on the second call, or the driver writes the
vendor blob to a null pointer.
Verified on SteamVR/PSVR2, VDXR/Quest 3, and Meta Link over repeated
open/close cycles.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This is a minor improvement to add line numbers to the LOG_VULKAN_ERROR
define. Basically error logs for Vulkan will now look like:
```
// This
25:03:347 VideoBackends/Vulkan/VulkanLoader.cpp:247 E[Video]: (WaitForCommandBufferCompletion:278) vkWaitForFences failed: (2: VK_TIMEOUT)
// Instead of
15:45:154 VideoBackends/Vulkan/VulkanLoader.cpp:247 E[Video]: (WaitForCommandBufferCompletion) vkWaitForFences failed: (2: VK_TIMEOUT)
```
Nothing currently uses it. It could theoretically be replaced with fmt support, but I don't think the LOG_VULKAN_ERROR macro is that useful and it'd be better to replace it with regular logging instead.
Per https://en.cppreference.com/w/cpp/preprocessor/replace#.23_and_.23.23_operators the `##` behavior is a nonstandard extension; this extension seems to be supported by all compilers we care about, but IntelliSense in visual studio doesn't correctly handle it, resulting in false errors in the IDE (but not when compiling).
Per https://en.cppreference.com/w/cpp/preprocessor/replace#Function-like_macros C++20 introduced a workaround, where `__VA_OPT__(, )` generates a comma if and only if `__VA_ARGS__` is non-empty.
This PR replaces all occurrences, with the exception of Externals, DSPSpy (which is not likely to be edited in MSVC and does not target C++20 currently), and JitArm64_Integer.cpp (which uses `Function(__VA_ARGS__)`, and thus does not ever need a comma).
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Since we are calling this off the UI thread, we can't use anything which
accesses the underlying NSView object. We create and set the Metal layer
on the UI thread before the video backend is initialized. This extension
is both compatible with MoltenVK and gfx-portability for accepting a
layer at surface creation.
The path to the MoltenVK library can be specified by the
LIBMOLTENVK_PATH environment variable, otherwise it assumes it is
located in the application bundle's Contents/MacOS directory.
This replaces usages of the non-standard __FUNCTION__ macro with the standard
mandated __func__ identifier.
__FUNCTION__ is a preprocessor definition that is provided as an
extension by compilers. This was the only convenient option to rely on
pre-C++11. However, C++11 and greater mandate the predefined identifier
__func__, which lets us accomplish the same thing.
The difference between the two, however, is that __func__ isn't a
preprocessor macro, it's an actual identifier that exists at function
scope. The C++17 draft standard (N4659) at section [dcl.fct.def.general]
paragraph 8 states:
"
The function-local predefined variable __func__ is defined as if a
definition of the form
static const char __func__[] = "function-name ";
had been provided, where function-name is an implementation-defined
string. It is unspecified whether such
a variable has an address distinct from that of any other object in the
program.
"
Thankfully, we don't do any macro or string concatenation with __FUNCTION__
that can't be modified to use __func__.
Jeremy Bowers