| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright 2016, Michael Ellerman, IBM Corp. |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/mman.h> |
| #include <unistd.h> |
| |
| #include <asm/cputable.h> |
| |
| #include "utils.h" |
| |
| #define SIZE (64 * 1024) |
| |
| int test_prot_sao(void) |
| { |
| char *p; |
| |
| /* |
| * SAO was introduced in 2.06 and removed in 3.1. It's disabled in |
| * guests/LPARs by default, so also skip if we are running in a guest. |
| */ |
| SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06) || |
| have_hwcap2(PPC_FEATURE2_ARCH_3_1) || |
| access("/proc/device-tree/rtas/ibm,hypertas-functions", F_OK) == 0); |
| |
| /* |
| * Ensure we can ask for PROT_SAO. |
| * We can't really verify that it does the right thing, but at least we |
| * confirm the kernel will accept it. |
| */ |
| p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE | PROT_SAO, |
| MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); |
| FAIL_IF(p == MAP_FAILED); |
| |
| /* Write to the mapping, to at least cause a fault */ |
| memset(p, 0xaa, SIZE); |
| |
| return 0; |
| } |
| |
| int main(void) |
| { |
| return test_harness(test_prot_sao, "prot-sao"); |
| } |
