mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-24 06:40:54 +07:00
a872eb2131
On powerpc, RODATA_TEST fails with message the following messages: Freeing unused kernel memory: 528K rodata_test: test data was not read only This is because GCC allocates it to .data section: c0695034 g O .data 00000004 rodata_test_data Since commit056b9d8a76("mm: remove rodata_test_data export, add pr_fmt"), rodata_test_data is used only inside rodata_test.c By declaring it static, it gets properly allocated into .rodata section instead of .data: c04df710 l O .rodata 00000004 rodata_test_data Fixes:056b9d8a76("mm: remove rodata_test_data export, add pr_fmt") Link: http://lkml.kernel.org/r/20170921093729.1080368AC1@po15668-vm-win7.idsi0.si.c-s.fr Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Kees Cook <keescook@chromium.org> Cc: Jinbum Park <jinb.park7@gmail.com> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: David Laight <David.Laight@ACULAB.COM> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
58 lines
1.4 KiB
C
58 lines
1.4 KiB
C
/*
|
|
* rodata_test.c: functional test for mark_rodata_ro function
|
|
*
|
|
* (C) Copyright 2008 Intel Corporation
|
|
* Author: Arjan van de Ven <arjan@linux.intel.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; version 2
|
|
* of the License.
|
|
*/
|
|
#define pr_fmt(fmt) "rodata_test: " fmt
|
|
|
|
#include <linux/uaccess.h>
|
|
#include <asm/sections.h>
|
|
|
|
static const int rodata_test_data = 0xC3;
|
|
|
|
void rodata_test(void)
|
|
{
|
|
unsigned long start, end;
|
|
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 (!probe_kernel_write((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 */
|
|
start = (unsigned long)__start_rodata;
|
|
end = (unsigned long)__end_rodata;
|
|
if (start & (PAGE_SIZE - 1)) {
|
|
pr_err("start of .rodata is not page size aligned\n");
|
|
return;
|
|
}
|
|
if (end & (PAGE_SIZE - 1)) {
|
|
pr_err("end of .rodata is not page size aligned\n");
|
|
return;
|
|
}
|
|
|
|
pr_info("all tests were successful\n");
|
|
}
|