Vulkan xlib issue

Graphics / Linux Linux
,
1

I have this weird issue where calling vkGetPhysicalDeviceSurfaceSupportKHR causes XCloseDisplay to segfault but it has some caveats:

  1. the physical device passed to vkGetPhysicalDeviceSurfaceSupportKHR is my nvidia gpu, I also have an intel hd graphics which does not trigger the crash
  2. it only happens if XCloseDisplay is called after vkDestroyInstance

Here’s an example of something similar to what I’m doing that also triggers the crash

#include <stdio.h>

#define VK_USE_PLATFORM_XLIB_KHR
#include <vulkan/vulkan.h>

int main(void) {
	Display* display = XOpenDisplay(NULL);
	if (display == NULL) {
		fprintf(stderr, "failed to connect to the X server\n");
		return -1;
	}

	Window window =XCreateWindow(
		display,
		DefaultRootWindow(display),
		0, 0,
		1280, 720,
		0,
		CopyFromParent,
		InputOutput,
		CopyFromParent,
		CWEventMask,
		&(XSetWindowAttributes) {
			.event_mask = ButtonPressMask | ButtonReleaseMask | PointerMotionMask |
				KeyPressMask | KeyReleaseMask | StructureNotifyMask,
		}
	);

	Atom WM_DELETE_WINDOW = XInternAtom(display, "WM_DELETE_WINDOW", False);
	XSetWMProtocols(display, window, &WM_DELETE_WINDOW, 1);

	XMapWindow(display, window);
	XFlush(display);

	char const* extensions[] = { VK_KHR_SURFACE_EXTENSION_NAME, VK_KHR_XLIB_SURFACE_EXTENSION_NAME };
	VkInstance instance = NULL;
	VkResult result = vkCreateInstance(
		&(VkInstanceCreateInfo) {
			.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO,
			.enabledExtensionCount = sizeof extensions / sizeof extensions[0],
			.ppEnabledExtensionNames = extensions,
			.pApplicationInfo = &(VkApplicationInfo) {
				.sType = VK_STRUCTURE_TYPE_APPLICATION_INFO,
				.apiVersion = VK_API_VERSION_1_0,
			}
		},
		NULL,
		&instance
	);
	VkSurfaceKHR surface = NULL;
	result = vkCreateXlibSurfaceKHR(
		instance,
		&(VkXlibSurfaceCreateInfoKHR) {
			.sType = VK_STRUCTURE_TYPE_XLIB_SURFACE_CREATE_INFO_KHR,
			.dpy = display,
			.window = window,
		},
		NULL,
		&surface
	);

	// device[0] is my nvidia gpu, device[1] is the intel gpu
	uint32_t device_count = 2;
	VkPhysicalDevice device[2];
	vkEnumeratePhysicalDevices(instance, &device_count, device);

	VkBool32 present_support = VK_FALSE;
	vkGetPhysicalDeviceSurfaceSupportKHR(device[0], 0, surface, &present_support);

	char close_requested = 0;
	while (!close_requested) {
		XEvent event = {0};
		while (XPending(display) > 0) {
			XNextEvent(display, &event);
			switch (event.type) {
				case ClientMessage: {
					if ((Atom)event.xclient.data.l[0] == WM_DELETE_WINDOW) {
						close_requested = 1;
					}
				} break;
				default: break;
			}
		}
	}
	vkDestroySurfaceKHR(instance, surface, NULL);
	vkDestroyInstance(instance, NULL);
	XCloseDisplay(display);
}