linux/mm/rodata_test.c
Xiu Jianfeng 679d7f69d6 mm/rodata_test: use PAGE_ALIGNED() helper
Use PAGE_ALIGNED() helper instead of open-coding operation, no functional
changes here.

Link: https://lkml.kernel.org/r/20220906075312.166595-1-xiujianfeng@huawei.com
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:05 -07:00

52 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* rodata_test.c: functional test for mark_rodata_ro function
*
* (C) Copyright 2008 Intel Corporation
* Author: Arjan van de Ven <arjan@linux.intel.com>
*/
#define pr_fmt(fmt) "rodata_test: " fmt
#include <linux/rodata_test.h>
#include <linux/uaccess.h>
#include <linux/mm.h>
#include <asm/sections.h>
static const int rodata_test_data = 0xC3;
void rodata_test(void)
{
int zero = 0;
/* test 1: read the value */
/* If this test fails, some previous testrun has clobbered the state */
if (!rodata_test_data) {
pr_err("test 1 fails (start data)\n");
return;
}
/* test 2: write to the variable; this should fault */
if (!copy_to_kernel_nofault((void *)&rodata_test_data,
(void *)&zero, sizeof(zero))) {
pr_err("test data was not read only\n");
return;
}
/* test 3: check the value hasn't changed */
if (rodata_test_data == zero) {
pr_err("test data was changed\n");
return;
}
/* test 4: check if the rodata section is PAGE_SIZE aligned */
if (!PAGE_ALIGNED(__start_rodata)) {
pr_err("start of .rodata is not page size aligned\n");
return;
}
if (!PAGE_ALIGNED(__end_rodata)) {
pr_err("end of .rodata is not page size aligned\n");
return;
}
pr_info("all tests were successful\n");
}