text: // SPDX-License-Identifier: GPL-2.0-only
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/export.h>
  #include <linux/mm.h>
  #include <linux/vmalloc.h>
  #include <linux/slab.h>
  #include <linux/sizes.h>
  #include <linux/io.h>
  
  #include <asm/page.h>
  #ifdef CONFIG_MIPS
  #include <asm/bootinfo.h>
  #endif
  
  struct foo {
  	unsigned int bar;
  };
  
  static struct foo *foo;
  
  static int __init test_debug_virtual_init(void)
  {
  	phys_addr_t pa;
  	void *va;
  
  	va = (void *)VMALLOC_START;
  	pa = virt_to_phys(va);
  
  	pr_info("PA: %pa for VA: 0x%lx\n", &pa, (unsigned long)va);
  
  	foo = kzalloc(sizeof(*foo), GFP_KERNEL);
  	if (!foo)
  		return -ENOMEM;
  
  	pa = virt_to_phys(foo);
  	va = foo;
  	pr_info("PA: %pa for VA: 0x%lx\n", &pa, (unsigned long)va);
  
  	return 0;
  }
  module_init(test_debug_virtual_init);
  
  static void __exit test_debug_virtual_exit(void)
  {
  	kfree(foo);
  }
  module_exit(test_debug_virtual_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("Test module for CONFIG_DEBUG_VIRTUAL");
  