Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * rodata_test.c: functional test for mark_rodata_ro function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * (C) Copyright 2008 Intel Corporation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  * Author: Arjan van de Ven <arjan@linux.intel.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #define pr_fmt(fmt) "rodata_test: " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/rodata_test.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <asm/sections.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) static const int rodata_test_data = 0xC3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) void rodata_test(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	unsigned long start, end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 	int zero = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	/* test 1: read the value */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	/* If this test fails, some previous testrun has clobbered the state */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	if (!rodata_test_data) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 		pr_err("test 1 fails (start data)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	/* test 2: write to the variable; this should fault */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	if (!copy_to_kernel_nofault((void *)&rodata_test_data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 				(void *)&zero, sizeof(zero))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 		pr_err("test data was not read only\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	/* test 3: check the value hasn't changed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	if (rodata_test_data == zero) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 		pr_err("test data was changed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	/* test 4: check if the rodata section is PAGE_SIZE aligned */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	start = (unsigned long)__start_rodata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	end = (unsigned long)__end_rodata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	if (start & (PAGE_SIZE - 1)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 		pr_err("start of .rodata is not page size aligned\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	if (end & (PAGE_SIZE - 1)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 		pr_err("end of .rodata is not page size aligned\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	pr_info("all tests were successful\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) }