From: Andy Lutomirski <luto@kernel.org>
Date: Sat, 31 Oct 2015 05:42:45 +0000 (-0700)
Subject: selftests/x86: Add a fork() to entry_from_vm86 to catch fork bugs
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=226f1f729ce277720fab60c91dd1b12574cfe66c;p=openwrt%2Fstaging%2Fblogic.git

selftests/x86: Add a fork() to entry_from_vm86 to catch fork bugs

Mere possession of vm86 state is strange.  Make sure that nothing
gets corrupted if we fork after calling vm86().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Stas Sergeev <stsp@list.ru>
Link: http://lkml.kernel.org/r/08f83295460a80e41dc5e3e81ec40d6844d316f5.1446270067.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/tools/testing/selftests/x86/entry_from_vm86.c b/tools/testing/selftests/x86/entry_from_vm86.c
index 421c607a8856..d075ea0e5ca1 100644
--- a/tools/testing/selftests/x86/entry_from_vm86.c
+++ b/tools/testing/selftests/x86/entry_from_vm86.c
@@ -230,5 +230,9 @@ int main(void)
 	}
 	clearhandler(SIGSEGV);
 
+	/* Make sure nothing explodes if we fork. */
+	if (fork() > 0)
+		return 0;
+
 	return (nerrs == 0 ? 0 : 1);
 }