![Paul Gortmaker](/assets/img/avatar_default.png)
The Kconfig controlling compilation of these files are: arch/x86/Kconfig.debug:config DEBUG_RODATA_TEST arch/x86/Kconfig.debug: bool "Testcase for the marking rodata read-only" arch/x86/Kconfig.debug:config X86_PTDUMP_CORE arch/x86/Kconfig.debug: def_bool n ...meaning that it currently is not being built as a module by anyone. Lets remove the couple traces of modular infrastructure use, so that when reading the driver there is no doubt it is builtin-only. We delete the MODULE_LICENSE tag etc. since all that information is already contained at the top of the file in the comments. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160714001901.31603-2-paul.gortmaker@windriver.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
76 lines
1.9 KiB
C
76 lines
1.9 KiB
C
/*
|
|
* test_rodata.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.
|
|
*/
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/asm.h>
|
|
|
|
int rodata_test(void)
|
|
{
|
|
unsigned long result;
|
|
unsigned long start, end;
|
|
|
|
/* test 1: read the value */
|
|
/* If this test fails, some previous testrun has clobbered the state */
|
|
if (!rodata_test_data) {
|
|
printk(KERN_ERR "rodata_test: test 1 fails (start data)\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* test 2: write to the variable; this should fault */
|
|
/*
|
|
* If this test fails, we managed to overwrite the data
|
|
*
|
|
* This is written in assembly to be able to catch the
|
|
* exception that is supposed to happen in the correct
|
|
* case
|
|
*/
|
|
|
|
result = 1;
|
|
asm volatile(
|
|
"0: mov %[zero],(%[rodata_test])\n"
|
|
" mov %[zero], %[rslt]\n"
|
|
"1:\n"
|
|
".section .fixup,\"ax\"\n"
|
|
"2: jmp 1b\n"
|
|
".previous\n"
|
|
_ASM_EXTABLE(0b,2b)
|
|
: [rslt] "=r" (result)
|
|
: [rodata_test] "r" (&rodata_test_data), [zero] "r" (0UL)
|
|
);
|
|
|
|
|
|
if (!result) {
|
|
printk(KERN_ERR "rodata_test: test data was not read only\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* test 3: check the value hasn't changed */
|
|
/* If this test fails, we managed to overwrite the data */
|
|
if (!rodata_test_data) {
|
|
printk(KERN_ERR "rodata_test: Test 3 fails (end data)\n");
|
|
return -ENODEV;
|
|
}
|
|
/* test 4: check if the rodata section is 4Kb aligned */
|
|
start = (unsigned long)__start_rodata;
|
|
end = (unsigned long)__end_rodata;
|
|
if (start & (PAGE_SIZE - 1)) {
|
|
printk(KERN_ERR "rodata_test: .rodata is not 4k aligned\n");
|
|
return -ENODEV;
|
|
}
|
|
if (end & (PAGE_SIZE - 1)) {
|
|
printk(KERN_ERR "rodata_test: .rodata end is not 4k aligned\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
return 0;
|
|
}
|