From a0968a025c04702427a4aee2c618f451a5098cd8 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Wed, 4 Mar 2020 22:04:02 +1100 Subject: selftests/powerpc: Add a test of sigreturn vs VDSO There's two different paths through the sigreturn code, depending on whether the VDSO is mapped or not. We recently discovered a bug in the unmapped case, because it's not commonly used these days. So add a test that sends itself a signal, then moves the VDSO, takes another signal and finally unmaps the VDSO before sending itself another signal. That tests the standard signal path, the code that handles the VDSO being moved, and also the signal path in the case where the VDSO is unmapped. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200304110402.6038-1-mpe@ellerman.id.au --- tools/testing/selftests/powerpc/signal/.gitignore | 1 + tools/testing/selftests/powerpc/signal/Makefile | 2 +- .../selftests/powerpc/signal/sigreturn_vdso.c | 127 +++++++++++++++++++++ 3 files changed, 129 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/powerpc/signal/sigreturn_vdso.c (limited to 'tools/testing/selftests/powerpc/signal') diff --git a/tools/testing/selftests/powerpc/signal/.gitignore b/tools/testing/selftests/powerpc/signal/.gitignore index dca5852a1546..03dafa795255 100644 --- a/tools/testing/selftests/powerpc/signal/.gitignore +++ b/tools/testing/selftests/powerpc/signal/.gitignore @@ -1,3 +1,4 @@ signal signal_tm sigfuz +sigreturn_vdso diff --git a/tools/testing/selftests/powerpc/signal/Makefile b/tools/testing/selftests/powerpc/signal/Makefile index 113838fbbe7f..63b57583e07d 100644 --- a/tools/testing/selftests/powerpc/signal/Makefile +++ b/tools/testing/selftests/powerpc/signal/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -TEST_GEN_PROGS := signal signal_tm sigfuz +TEST_GEN_PROGS := signal signal_tm sigfuz sigreturn_vdso CFLAGS += -maltivec $(OUTPUT)/signal_tm: CFLAGS += -mhtm diff --git a/tools/testing/selftests/powerpc/signal/sigreturn_vdso.c b/tools/testing/selftests/powerpc/signal/sigreturn_vdso.c new file mode 100644 index 000000000000..e282fff0fe25 --- /dev/null +++ b/tools/testing/selftests/powerpc/signal/sigreturn_vdso.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test that we can take signals with and without the VDSO mapped, which trigger + * different paths in the signal handling code. + * + * See handle_rt_signal64() and setup_trampoline() in signal_64.c + */ + +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include +#include + +// Ensure assert() is not compiled out +#undef NDEBUG +#include + +#include "utils.h" + +static int search_proc_maps(char *needle, unsigned long *low, unsigned long *high) +{ + unsigned long start, end; + static char buf[4096]; + char name[128]; + FILE *f; + int rc = -1; + + f = fopen("/proc/self/maps", "r"); + if (!f) { + perror("fopen"); + return -1; + } + + while (fgets(buf, sizeof(buf), f)) { + rc = sscanf(buf, "%lx-%lx %*c%*c%*c%*c %*x %*d:%*d %*d %127s\n", + &start, &end, name); + if (rc == 2) + continue; + + if (rc != 3) { + printf("sscanf errored\n"); + rc = -1; + break; + } + + if (strstr(name, needle)) { + *low = start; + *high = end - 1; + rc = 0; + break; + } + } + + fclose(f); + + return rc; +} + +static volatile sig_atomic_t took_signal = 0; + +static void sigusr1_handler(int sig) +{ + took_signal++; +} + +int test_sigreturn_vdso(void) +{ + unsigned long low, high, size; + struct sigaction act; + char *p; + + act.sa_handler = sigusr1_handler; + act.sa_flags = 0; + sigemptyset(&act.sa_mask); + + assert(sigaction(SIGUSR1, &act, NULL) == 0); + + // Confirm the VDSO is mapped, and work out where it is + assert(search_proc_maps("[vdso]", &low, &high) == 0); + size = high - low + 1; + printf("VDSO is at 0x%lx-0x%lx (%lu bytes)\n", low, high, size); + + kill(getpid(), SIGUSR1); + assert(took_signal == 1); + printf("Signal delivered OK with VDSO mapped\n"); + + // Remap the VDSO somewhere else + p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); + assert(p != MAP_FAILED); + assert(mremap((void *)low, size, size, MREMAP_MAYMOVE|MREMAP_FIXED, p) != MAP_FAILED); + assert(search_proc_maps("[vdso]", &low, &high) == 0); + size = high - low + 1; + printf("VDSO moved to 0x%lx-0x%lx (%lu bytes)\n", low, high, size); + + kill(getpid(), SIGUSR1); + assert(took_signal == 2); + printf("Signal delivered OK with VDSO moved\n"); + + assert(munmap((void *)low, size) == 0); + printf("Unmapped VDSO\n"); + + // Confirm the VDSO is not mapped anymore + assert(search_proc_maps("[vdso]", &low, &high) != 0); + + // Make the stack executable + assert(search_proc_maps("[stack]", &low, &high) == 0); + size = high - low + 1; + mprotect((void *)low, size, PROT_READ|PROT_WRITE|PROT_EXEC); + printf("Remapped the stack executable\n"); + + kill(getpid(), SIGUSR1); + assert(took_signal == 3); + printf("Signal delivered OK with VDSO unmapped\n"); + + return 0; +} + +int main(void) +{ + return test_harness(test_sigreturn_vdso, "sigreturn_vdso"); +} -- cgit v1.2.3 From 850507f30c38dff21ed557cb98ab16db26c32bbc Mon Sep 17 00:00:00 2001 From: Po-Hsu Lin Date: Wed, 18 Mar 2020 14:00:04 +0800 Subject: selftests/powerpc: Turn off timeout setting for benchmarks, dscr, signal, tm Some specific tests in powerpc can take longer than the default 45 seconds that added in commit 852c8cbf34d3 ("selftests/kselftest/runner.sh: Add 45 second timeout per test") to run, the following test result was collected across 2 Power8 nodes and 1 Power9 node in our pool: powerpc/benchmarks/futex_bench - 52s powerpc/dscr/dscr_sysfs_test - 116s powerpc/signal/signal_fuzzer - 88s powerpc/tm/tm_unavailable_test - 168s powerpc/tm/tm-poison - 240s Thus they will fail with TIMEOUT error. Disable the timeout setting for these sub-tests to allow them finish properly. https://bugs.launchpad.net/bugs/1864642 Fixes: 852c8cbf34d3 ("selftests/kselftest/runner.sh: Add 45 second timeout per test") Signed-off-by: Po-Hsu Lin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200318060004.10685-1-po-hsu.lin@canonical.com --- tools/testing/selftests/powerpc/benchmarks/Makefile | 2 ++ tools/testing/selftests/powerpc/benchmarks/settings | 1 + tools/testing/selftests/powerpc/dscr/Makefile | 2 ++ tools/testing/selftests/powerpc/dscr/settings | 1 + tools/testing/selftests/powerpc/signal/Makefile | 2 ++ tools/testing/selftests/powerpc/signal/settings | 1 + tools/testing/selftests/powerpc/tm/Makefile | 2 ++ tools/testing/selftests/powerpc/tm/settings | 1 + 8 files changed, 12 insertions(+) create mode 100644 tools/testing/selftests/powerpc/benchmarks/settings create mode 100644 tools/testing/selftests/powerpc/dscr/settings create mode 100644 tools/testing/selftests/powerpc/signal/settings create mode 100644 tools/testing/selftests/powerpc/tm/settings (limited to 'tools/testing/selftests/powerpc/signal') diff --git a/tools/testing/selftests/powerpc/benchmarks/Makefile b/tools/testing/selftests/powerpc/benchmarks/Makefile index d40300a65b42..a32a6ab89914 100644 --- a/tools/testing/selftests/powerpc/benchmarks/Makefile +++ b/tools/testing/selftests/powerpc/benchmarks/Makefile @@ -2,6 +2,8 @@ TEST_GEN_PROGS := gettimeofday context_switch fork mmap_bench futex_bench null_syscall TEST_GEN_FILES := exec_target +TEST_FILES := settings + CFLAGS += -O2 top_srcdir = ../../../../.. diff --git a/tools/testing/selftests/powerpc/benchmarks/settings b/tools/testing/selftests/powerpc/benchmarks/settings new file mode 100644 index 000000000000..e7b9417537fb --- /dev/null +++ b/tools/testing/selftests/powerpc/benchmarks/settings @@ -0,0 +1 @@ +timeout=0 diff --git a/tools/testing/selftests/powerpc/dscr/Makefile b/tools/testing/selftests/powerpc/dscr/Makefile index 5df476364b4d..cfa6eedcb66c 100644 --- a/tools/testing/selftests/powerpc/dscr/Makefile +++ b/tools/testing/selftests/powerpc/dscr/Makefile @@ -3,6 +3,8 @@ TEST_GEN_PROGS := dscr_default_test dscr_explicit_test dscr_user_test \ dscr_inherit_test dscr_inherit_exec_test dscr_sysfs_test \ dscr_sysfs_thread_test +TEST_FILES := settings + top_srcdir = ../../../../.. include ../../lib.mk diff --git a/tools/testing/selftests/powerpc/dscr/settings b/tools/testing/selftests/powerpc/dscr/settings new file mode 100644 index 000000000000..e7b9417537fb --- /dev/null +++ b/tools/testing/selftests/powerpc/dscr/settings @@ -0,0 +1 @@ +timeout=0 diff --git a/tools/testing/selftests/powerpc/signal/Makefile b/tools/testing/selftests/powerpc/signal/Makefile index 63b57583e07d..932a032bf036 100644 --- a/tools/testing/selftests/powerpc/signal/Makefile +++ b/tools/testing/selftests/powerpc/signal/Makefile @@ -5,6 +5,8 @@ CFLAGS += -maltivec $(OUTPUT)/signal_tm: CFLAGS += -mhtm $(OUTPUT)/sigfuz: CFLAGS += -pthread -m64 +TEST_FILES := settings + top_srcdir = ../../../../.. include ../../lib.mk diff --git a/tools/testing/selftests/powerpc/signal/settings b/tools/testing/selftests/powerpc/signal/settings new file mode 100644 index 000000000000..e7b9417537fb --- /dev/null +++ b/tools/testing/selftests/powerpc/signal/settings @@ -0,0 +1 @@ +timeout=0 diff --git a/tools/testing/selftests/powerpc/tm/Makefile b/tools/testing/selftests/powerpc/tm/Makefile index b1d99736f8b8..0b0db8d3857c 100644 --- a/tools/testing/selftests/powerpc/tm/Makefile +++ b/tools/testing/selftests/powerpc/tm/Makefile @@ -7,6 +7,8 @@ TEST_GEN_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack $(SIGNAL_CONTEXT_CHK_TESTS) tm-sigreturn tm-signal-sigreturn-nt \ tm-signal-context-force-tm tm-poison tm-signal-pagefault +TEST_FILES := settings + top_srcdir = ../../../../.. include ../../lib.mk diff --git a/tools/testing/selftests/powerpc/tm/settings b/tools/testing/selftests/powerpc/tm/settings new file mode 100644 index 000000000000..e7b9417537fb --- /dev/null +++ b/tools/testing/selftests/powerpc/tm/settings @@ -0,0 +1 @@ +timeout=0 -- cgit v1.2.3