The idea is to ease automated testing under qemu. If the test succeeds while running as PID 1, indicating the system was booted with init=/test, let's just power off so that qemu can exit with a successful code. In other situations it will exit and provoke a panic, which may be caught for example with CONFIG_PVPANIC. Signed-off-by: Willy Tarreau <w@xxxxxx> --- tools/testing/selftests/nolibc/nolibc-test.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c index ab7c4cbdef9b..5f2173610d03 100644 --- a/tools/testing/selftests/nolibc/nolibc-test.c +++ b/tools/testing/selftests/nolibc/nolibc-test.c @@ -626,6 +626,20 @@ int main(int argc, char **argv, char **envp) } printf("Total number of errors: %d\n", ret); + + if (getpid() == 1) { + /* we're running as init, there's no other process on the + * system, thus likely started from a VM for a quick check. + * Exiting will provoke a kernel panic that may be reported + * as an error by Qemu or the hypervisor, while stopping + * cleanly will often be reported as a success. This allows + * to use the output of this program for bisecting kernels. + */ + printf("Leaving init with final status: %d\n", !!ret); + if (ret == 0) + reboot(LINUX_REBOOT_CMD_POWER_OFF); + } + printf("Exiting with status %d\n", !!ret); return !!ret; } -- 2.17.5