From 5750895ee785ec6f61b36a92a69e945748208d87 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 16 Jul 2019 16:26:36 -0700 Subject: [PATCH] tools/testing/selftests/proc/proc-pid-vm.c: hide "segfault at ffffffffff600000" dmesg spam Test tries to access vsyscall page and if it doesn't exist gets SIGSEGV which can spam into dmesg. However the segfault happens by design. Handle it and carry information via exit code to parent. Link: http://lkml.kernel.org/r/20190524181256.GA2260@avx2 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- tools/testing/selftests/proc/proc-pid-vm.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/proc/proc-pid-vm.c b/tools/testing/selftests/proc/proc-pid-vm.c index 853aa164a401e..18a3bde8bc961 100644 --- a/tools/testing/selftests/proc/proc-pid-vm.c +++ b/tools/testing/selftests/proc/proc-pid-vm.c @@ -215,6 +215,11 @@ static const char str_vsyscall[] = "ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]\n"; #ifdef __x86_64__ +static void sigaction_SIGSEGV(int _, siginfo_t *__, void *___) +{ + _exit(1); +} + /* * vsyscall page can't be unmapped, probe it with memory load. */ @@ -231,11 +236,19 @@ static void vsyscall(void) if (pid == 0) { struct rlimit rlim = {0, 0}; (void)setrlimit(RLIMIT_CORE, &rlim); + + /* Hide "segfault at ffffffffff600000" messages. */ + struct sigaction act; + memset(&act, 0, sizeof(struct sigaction)); + act.sa_flags = SA_SIGINFO; + act.sa_sigaction = sigaction_SIGSEGV; + (void)sigaction(SIGSEGV, &act, NULL); + *(volatile int *)0xffffffffff600000UL; exit(0); } - wait(&wstatus); - if (WIFEXITED(wstatus)) { + waitpid(pid, &wstatus, 0); + if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) == 0) { g_vsyscall = true; } } -- 2.39.5