 7bfeab9af9
			
		
	
	
	7bfeab9af9
	
	
	
		
			
			extern should not appear in C files. Also, the definitions do not match the prototype currently, not sure what way you want to go with this, I've switched the prototype to return int, but I can see going to the void return as well. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
		
			
				
	
	
		
			86 lines
		
	
	
	
		
			2.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			86 lines
		
	
	
	
		
			2.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * test_rodata.c: functional test for mark_rodata_ro function
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|  *
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|  * (C) Copyright 2008 Intel Corporation
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|  * Author: Arjan van de Ven <arjan@linux.intel.com>
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License
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|  * as published by the Free Software Foundation; version 2
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|  * of the License.
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|  */
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| #include <linux/module.h>
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| #include <asm/cacheflush.h>
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| #include <asm/sections.h>
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| 
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| int rodata_test(void)
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| {
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| 	unsigned long result;
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| 	unsigned long start, end;
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| 
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| 	/* test 1: read the value */
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| 	/* If this test fails, some previous testrun has clobbered the state */
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| 	if (!rodata_test_data) {
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| 		printk(KERN_ERR "rodata_test: test 1 fails (start data)\n");
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| 		return -ENODEV;
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| 	}
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| 
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| 	/* test 2: write to the variable; this should fault */
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| 	/*
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| 	 * If this test fails, we managed to overwrite the data
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| 	 *
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| 	 * This is written in assembly to be able to catch the
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| 	 * exception that is supposed to happen in the correct
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| 	 * case
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| 	 */
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| 
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| 	result = 1;
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| 	asm volatile(
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| 		"0:	mov %[zero],(%[rodata_test])\n"
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| 		"	mov %[zero], %[rslt]\n"
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| 		"1:\n"
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| 		".section .fixup,\"ax\"\n"
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| 		"2:	jmp 1b\n"
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| 		".previous\n"
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| 		".section __ex_table,\"a\"\n"
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| 		"       .align 16\n"
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| #ifdef CONFIG_X86_32
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| 		"	.long 0b,2b\n"
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| #else
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| 		"	.quad 0b,2b\n"
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| #endif
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| 		".previous"
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| 		: [rslt] "=r" (result)
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| 		: [rodata_test] "r" (&rodata_test_data), [zero] "r" (0UL)
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| 	);
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| 
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| 
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| 	if (!result) {
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| 		printk(KERN_ERR "rodata_test: test data was not read only\n");
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| 		return -ENODEV;
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| 	}
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| 
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| 	/* test 3: check the value hasn't changed */
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| 	/* If this test fails, we managed to overwrite the data */
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| 	if (!rodata_test_data) {
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| 		printk(KERN_ERR "rodata_test: Test 3 failes (end data)\n");
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| 		return -ENODEV;
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| 	}
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| 	/* test 4: check if the rodata section is 4Kb aligned */
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| 	start = (unsigned long)__start_rodata;
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| 	end = (unsigned long)__end_rodata;
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| 	if (start & (PAGE_SIZE - 1)) {
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| 		printk(KERN_ERR "rodata_test: .rodata is not 4k aligned\n");
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| 		return -ENODEV;
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| 	}
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| 	if (end & (PAGE_SIZE - 1)) {
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| 		printk(KERN_ERR "rodata_test: .rodata end is not 4k aligned\n");
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| 		return -ENODEV;
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| MODULE_LICENSE("GPL");
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| MODULE_DESCRIPTION("Testcase for the DEBUG_RODATA infrastructure");
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| MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
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