tools/nolibc/test: on x86, support exiting with isa-debug-exit
QEMU, when started with "-device isa-debug-exit -no-reboot" will exit
with status code 2N+1 when N is written to 0x501. This is particularly
convenient for automated tests but this is not portable. As such we
only enable this on x86_64 when pid==1. In addition, this requires an
ioperm() call but in order not to have to define arch-specific syscalls
we just perform the syscall by hand there.
Signed-off-by: Willy Tarreau <w@1wt.eu>
diff --git a/tools/include/nolibc/test/nolibc-test.c b/tools/include/nolibc/test/nolibc-test.c
index be3aeb5..f52a10c 100644
--- a/tools/include/nolibc/test/nolibc-test.c
+++ b/tools/include/nolibc/test/nolibc-test.c
@@ -531,6 +531,15 @@
*/
if (ret == 0)
reboot(LINUX_REBOOT_CMD_POWER_OFF);
+#if defined(__x86_64__)
+ /* QEMU started with "-device isa-debug-exit -no-reboot" will
+ * exit with status code 2N+1 when N is written to 0x501. We
+ * hard-code the syscall here as it's arch-dependent.
+ */
+ else if (my_syscall3(__NR_ioperm, 0x501, 1, 1) == 0)
+ asm volatile ("outb %%al, %%dx" :: "d"(0x501), "a"(0));
+ /* if it does nothing, fall back to the regular panic */
+#endif
}
printf("Exiting with status %d\n", ret);
return ret;