linux/lib/test_free_pages.c
Linus Walleij b3c56f8f20 lib/test_free_pages.c: pass a pointer to virt_to_page()
In a recent change to the Arm architecture with the end goal of removing
highmem we need to convert virt_to_phys() and virt_to_pfn() to static
inline functions.

This will make them strongly typed.

However since virt_to_* is always implemented as macros they have become
polymorphic and accept both (void *) and e.g.  unsigned long as arguments.

Other functions such as virt_to_page() simply wrap virt_to_pfn() and get
affected indirectly.

To be able to proceed, patch mm to use (void *) as argument to affected
functions in all instances.


This patch (of 5):

A pointer into virtual memory is represented by a (void *) not an u32, so
the compiler warns:

lib/test_free_pages.c:20:50: warning: passing argument 1
  of 'virt_to_pfn' makes pointer from integer without a
  cast [-Wint-conversion]

Fix this with an explicit cast.

Link: https://lkml.kernel.org/r/20220630084124.691207-1-linus.walleij@linaro.org
Link: https://lkml.kernel.org/r/20220630084124.691207-2-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:36 -07:00

47 lines
1,003 B
C

// SPDX-License-Identifier: GPL-2.0+
/*
* test_free_pages.c: Check that free_pages() doesn't leak memory
* Copyright (c) 2020 Oracle
* Author: Matthew Wilcox <willy@infradead.org>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/module.h>
static void test_free_pages(gfp_t gfp)
{
unsigned int i;
for (i = 0; i < 1000 * 1000; i++) {
unsigned long addr = __get_free_pages(gfp, 3);
struct page *page = virt_to_page((void *)addr);
/* Simulate page cache getting a speculative reference */
get_page(page);
free_pages(addr, 3);
put_page(page);
}
}
static int m_in(void)
{
pr_info("Testing with GFP_KERNEL\n");
test_free_pages(GFP_KERNEL);
pr_info("Testing with GFP_KERNEL | __GFP_COMP\n");
test_free_pages(GFP_KERNEL | __GFP_COMP);
pr_info("Test completed\n");
return 0;
}
static void m_ex(void)
{
}
module_init(m_in);
module_exit(m_ex);
MODULE_AUTHOR("Matthew Wilcox <willy@infradead.org>");
MODULE_LICENSE("GPL");