check: prctl -- Add PR_SET_MM_AUXV test

The ability to set PR_SET_MM_AUXV is implemented
in kernel as a separate PR_SET_MM extension, so
we need to test if the kernel patch is applied
on a running system.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-check.c

@@ -77,6 +77,7 @@ static int check_kcmp(void)
 
 static int check_prctl(void)
 {
+	unsigned long user_auxv = 0;
 	unsigned int *tid_addr;
 	int ret;
 
@@ -98,6 +99,12 @@ static int check_prctl(void)
 		return -1;
 	}
 
+	ret = sys_prctl(PR_SET_MM, PR_SET_MM_AUXV, (long)&user_auxv, sizeof(user_auxv), 0);
+	if (ret) {
+		pr_msg("prctl: PR_SET_MM_AUXV is not supported\n");
+		return -1;
+	}
+
 	return 0;
 }