x86: nmi - unify die_nmi() interface

By slightly changing 32bit mode die_nmi() we may unify the
interface and make it common for both (32/64bit) modes
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: hpa@zytor.com
Cc: mingo@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/nmi_32.c

@@ -320,8 +320,6 @@ void touch_nmi_watchdog(void)
 }
 EXPORT_SYMBOL(touch_nmi_watchdog);
 
-extern void die_nmi(struct pt_regs *, const char *msg);
-
 notrace __kprobes int
 nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
 {
@@ -375,7 +373,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
 			/*
 			 * die_nmi will return ONLY if NOTIFY_STOP happens..
 			 */
-			die_nmi(regs, "BUG: NMI Watchdog detected LOCKUP");
+			die_nmi("BUG: NMI Watchdog detected LOCKUP",
+				regs, 0);
 	} else {
 		__get_cpu_var(last_irq_sum) = sum;
 		local_set(&__get_cpu_var(alert_counter), 0);
@@ -406,7 +405,7 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu)
 	char buf[64];
 
 	sprintf(buf, "NMI received for unknown reason %02x\n", reason);
-	die_nmi(regs, buf);
+	die_nmi(buf, regs, 0);
 	return 0;
 }
 

arch/x86/kernel/traps_32.c

@@ -755,9 +755,9 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs)
 
 static DEFINE_SPINLOCK(nmi_print_lock);
 
-void notrace __kprobes die_nmi(struct pt_regs *regs, const char *msg)
+void notrace __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic)
 {
-	if (notify_die(DIE_NMIWATCHDOG, msg, regs, 0, 2, SIGINT) == NOTIFY_STOP)
+	if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
 		return;
 
 	spin_lock(&nmi_print_lock);
@@ -766,10 +766,12 @@ void notrace __kprobes die_nmi(struct pt_regs *regs, const char *msg)
 	* to get a message out:
 	*/
 	bust_spinlocks(1);
-	printk(KERN_EMERG "%s", msg);
+	printk(KERN_EMERG "%s", str);
 	printk(" on CPU%d, ip %08lx, registers:\n",
 		smp_processor_id(), regs->ip);
 	show_registers(regs);
+	if (do_panic)
+		panic("Non maskable interrupt");
 	console_silent();
 	spin_unlock(&nmi_print_lock);
 	bust_spinlocks(0);

include/asm-x86/nmi.h

@@ -38,12 +38,12 @@ static inline void unset_nmi_pm_callback(struct pm_dev *dev)
 
 #ifdef CONFIG_X86_64
 extern void default_do_nmi(struct pt_regs *);
-extern void die_nmi(char *str, struct pt_regs *regs, int do_panic);
 extern void nmi_watchdog_default(void);
 #else
 #define nmi_watchdog_default() do {} while (0)
 #endif
 
+extern void die_nmi(char *str, struct pt_regs *regs, int do_panic);
 extern int check_nmi_watchdog(void);
 extern int nmi_watchdog_enabled;
 extern int avail_to_resrv_perfctr_nmi_bit(unsigned int);