selftests/x86/vm86: Fix entry_from_vm86 test on 64-bit kernels

The test failed due to an oversight on my part when run on a
64-bit kernel.  vm86 isn't expected to work at all, and I
mistakenly failed one part of the test because no signal was
delivered.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/502c8bef877b33fe4943885ded6125dfcc7892db.1438205722.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/tools/testing/selftests/x86/entry_from_vm86.c b/tools/testing/selftests/x86/entry_from_vm86.c
index f004b2a..9a43a59 100644 (file)
--- a/tools/testing/selftests/x86/entry_from_vm86.c
+++ b/tools/testing/selftests/x86/entry_from_vm86.c
@@ -105,7 +105,8 @@ extern unsigned char vmcode[], end_vmcode[];
 extern unsigned char vmcode_bound[], vmcode_sysenter[], vmcode_syscall[],
        vmcode_sti[], vmcode_int3[], vmcode_int80[];
 
-static void do_test(struct vm86plus_struct *v86, unsigned long eip,
+/* Returns false if the test was skipped. */
+static bool do_test(struct vm86plus_struct *v86, unsigned long eip,
                    unsigned int rettype, unsigned int retarg,
                    const char *text)
 {
@@ -117,7 +118,7 @@ static void do_test(struct vm86plus_struct *v86, unsigned long eip,
 
        if (ret == -1 && errno == ENOSYS) {
                printf("[SKIP]\tvm86 not supported\n");
-               return;
+               return false;
        }
 
        if (VM86_TYPE(ret) == VM86_INTx) {
@@ -154,6 +155,8 @@ static void do_test(struct vm86plus_struct *v86, unsigned long eip,
                printf("[FAIL]\tIncorrect return reason\n");
                nerrs++;
        }
+
+       return true;
 }
 
 int main(void)
@@ -219,8 +222,8 @@ int main(void)
        v86.regs.ss = 0;
        sethandler(SIGSEGV, sighandler, 0);
        got_signal = 0;
-       do_test(&v86, 0, VM86_SIGNAL, 0, "Execute null pointer");
-       if (!got_signal) {
+       if (do_test(&v86, 0, VM86_SIGNAL, 0, "Execute null pointer") &&
+           !got_signal) {
                printf("[FAIL]\tDid not receive SIGSEGV\n");
                nerrs++;
        }