This patch silences the following sparse warning:
arch/x86/kernel/vsyscall_64.c:250:34:
       warning: Using plain integer as NULL pointer
Signed-off-by: Emil Goode <emilgoode@gmail.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: john.stultz@linaro.org
Link: http://lkml.kernel.org/r/1333306084-3776-1-git-send-email-emilgoode@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
 
        current_thread_info()->sig_on_uaccess_error = 1;
 
        /*
-        * 0 is a valid user pointer (in the access_ok sense) on 32-bit and
+        * NULL is a valid user pointer (in the access_ok sense) on 32-bit and
         * 64-bit, so we don't need to special-case it here.  For all the
-        * vsyscalls, 0 means "don't write anything" not "write it at
+        * vsyscalls, NULL means "don't write anything" not "write it at
         * address 0".
         */
        ret = -EFAULT;
 
                ret = sys_getcpu((unsigned __user *)regs->di,
                                 (unsigned __user *)regs->si,
-                                0);
+                                NULL);
                break;
        }