diff options
4 files changed, 176 insertions, 1 deletions
diff --git a/tools/testing/selftests/powerpc/security/Makefile b/tools/testing/selftests/powerpc/security/Makefile index f25e854fe370..844d18cd5f93 100644 --- a/tools/testing/selftests/powerpc/security/Makefile +++ b/tools/testing/selftests/powerpc/security/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0+ -TEST_GEN_PROGS := rfi_flush entry_flush spectre_v2 +TEST_GEN_PROGS := rfi_flush entry_flush uaccess_flush spectre_v2 top_srcdir = ../../../../.. CFLAGS += -I../../../../../usr/include @@ -13,3 +13,4 @@ $(OUTPUT)/spectre_v2: CFLAGS += -m64 $(OUTPUT)/spectre_v2: ../pmu/event.c branch_loops.S $(OUTPUT)/rfi_flush: flush_utils.c $(OUTPUT)/entry_flush: flush_utils.c +$(OUTPUT)/uaccess_flush: flush_utils.c diff --git a/tools/testing/selftests/powerpc/security/flush_utils.c b/tools/testing/selftests/powerpc/security/flush_utils.c index 0c3c4c40c7fb..4d95965cb751 100644 --- a/tools/testing/selftests/powerpc/security/flush_utils.c +++ b/tools/testing/selftests/powerpc/security/flush_utils.c @@ -13,6 +13,7 @@ #include <stdlib.h> #include <string.h> #include <stdio.h> +#include <sys/utsname.h> #include "utils.h" #include "flush_utils.h" @@ -35,6 +36,18 @@ void syscall_loop(char *p, unsigned long iterations, } } +void syscall_loop_uaccess(char *p, unsigned long iterations, + unsigned long zero_size) +{ + struct utsname utsname; + + for (unsigned long i = 0; i < iterations; i++) { + for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE) + load(p + j); + uname(&utsname); + } +} + static void sigill_handler(int signr, siginfo_t *info, void *unused) { static int warned; diff --git a/tools/testing/selftests/powerpc/security/flush_utils.h b/tools/testing/selftests/powerpc/security/flush_utils.h index 7a3d60292916..e1e68281f7ac 100644 --- a/tools/testing/selftests/powerpc/security/flush_utils.h +++ b/tools/testing/selftests/powerpc/security/flush_utils.h @@ -16,6 +16,9 @@ void syscall_loop(char *p, unsigned long iterations, unsigned long zero_size); +void syscall_loop_uaccess(char *p, unsigned long iterations, + unsigned long zero_size); + void set_dscr(unsigned long val); #endif /* _SELFTESTS_POWERPC_SECURITY_FLUSH_UTILS_H */ diff --git a/tools/testing/selftests/powerpc/security/uaccess_flush.c b/tools/testing/selftests/powerpc/security/uaccess_flush.c new file mode 100644 index 000000000000..cf80f960e38a --- /dev/null +++ b/tools/testing/selftests/powerpc/security/uaccess_flush.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0+ + +/* + * Copyright 2018 IBM Corporation. + * Copyright 2020 Canonical Ltd. + */ + +#define __SANE_USERSPACE_TYPES__ + +#include <sys/types.h> +#include <stdint.h> +#include <malloc.h> +#include <unistd.h> +#include <signal.h> +#include <stdlib.h> +#include <string.h> +#include <stdio.h> +#include "utils.h" +#include "flush_utils.h" + +int uaccess_flush_test(void) +{ + char *p; + int repetitions = 10; + int fd, passes = 0, iter, rc = 0; + struct perf_event_read v; + __u64 l1d_misses_total = 0; + unsigned long iterations = 100000, zero_size = 24 * 1024; + unsigned long l1d_misses_expected; + int rfi_flush_orig; + int entry_flush_orig; + int uaccess_flush, uaccess_flush_orig; + + SKIP_IF(geteuid() != 0); + + // The PMU event we use only works on Power7 or later + SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06)); + + if (read_debugfs_file("powerpc/rfi_flush", &rfi_flush_orig) < 0) { + perror("Unable to read powerpc/rfi_flush debugfs file"); + SKIP_IF(1); + } + + if (read_debugfs_file("powerpc/entry_flush", &entry_flush_orig) < 0) { + perror("Unable to read powerpc/entry_flush debugfs file"); + SKIP_IF(1); + } + + if (read_debugfs_file("powerpc/uaccess_flush", &uaccess_flush_orig) < 0) { + perror("Unable to read powerpc/entry_flush debugfs file"); + SKIP_IF(1); + } + + if (rfi_flush_orig != 0) { + if (write_debugfs_file("powerpc/rfi_flush", 0) < 0) { + perror("error writing to powerpc/rfi_flush debugfs file"); + FAIL_IF(1); + } + } + + if (entry_flush_orig != 0) { + if (write_debugfs_file("powerpc/entry_flush", 0) < 0) { + perror("error writing to powerpc/entry_flush debugfs file"); + FAIL_IF(1); + } + } + + uaccess_flush = uaccess_flush_orig; + + fd = perf_event_open_counter(PERF_TYPE_HW_CACHE, PERF_L1D_READ_MISS_CONFIG, -1); + FAIL_IF(fd < 0); + + p = (char *)memalign(zero_size, CACHELINE_SIZE); + + FAIL_IF(perf_event_enable(fd)); + + // disable L1 prefetching + set_dscr(1); + + iter = repetitions; + + /* + * We expect to see l1d miss for each cacheline access when entry_flush + * is set. Allow a small variation on this. + */ + l1d_misses_expected = iterations * (zero_size / CACHELINE_SIZE - 2); + +again: + FAIL_IF(perf_event_reset(fd)); + + syscall_loop_uaccess(p, iterations, zero_size); + + FAIL_IF(read(fd, &v, sizeof(v)) != sizeof(v)); + + if (uaccess_flush && v.l1d_misses >= l1d_misses_expected) + passes++; + else if (!uaccess_flush && v.l1d_misses < (l1d_misses_expected / 2)) + passes++; + + l1d_misses_total += v.l1d_misses; + + while (--iter) + goto again; + + if (passes < repetitions) { + printf("FAIL (L1D misses with uaccess_flush=%d: %llu %c %lu) [%d/%d failures]\n", + uaccess_flush, l1d_misses_total, uaccess_flush ? '<' : '>', + uaccess_flush ? repetitions * l1d_misses_expected : + repetitions * l1d_misses_expected / 2, + repetitions - passes, repetitions); + rc = 1; + } else { + printf("PASS (L1D misses with uaccess_flush=%d: %llu %c %lu) [%d/%d pass]\n", + uaccess_flush, l1d_misses_total, uaccess_flush ? '>' : '<', + uaccess_flush ? repetitions * l1d_misses_expected : + repetitions * l1d_misses_expected / 2, + passes, repetitions); + } + + if (uaccess_flush == uaccess_flush_orig) { + uaccess_flush = !uaccess_flush_orig; + if (write_debugfs_file("powerpc/uaccess_flush", uaccess_flush) < 0) { + perror("error writing to powerpc/uaccess_flush debugfs file"); + return 1; + } + iter = repetitions; + l1d_misses_total = 0; + passes = 0; + goto again; + } + + perf_event_disable(fd); + close(fd); + + set_dscr(0); + + if (write_debugfs_file("powerpc/rfi_flush", rfi_flush_orig) < 0) { + perror("unable to restore original value of powerpc/rfi_flush debugfs file"); + return 1; + } + + if (write_debugfs_file("powerpc/entry_flush", entry_flush_orig) < 0) { + perror("unable to restore original value of powerpc/entry_flush debugfs file"); + return 1; + } + + if (write_debugfs_file("powerpc/uaccess_flush", uaccess_flush_orig) < 0) { + perror("unable to restore original value of powerpc/uaccess_flush debugfs file"); + return 1; + } + + return rc; +} + +int main(int argc, char *argv[]) +{ + return test_harness(uaccess_flush_test, "uaccess_flush_test"); +} |