x86: nmi - consolidate nmi_watchdog_default for 32bit mode

64bit mode bootstrap code does set nmi_watchdog to NMI_NONE
by default and doing the same on 32bit mode is safe too.
Such an action saves us from several #ifdef.

Btw, my previous commit

commit 19ec673ced067316b9732bc6d1c4ff4052e5f795
Author: Cyrill Gorcunov <gorcunov@gmail.com>
Date:   Wed May 28 23:00:47 2008 +0400

    x86: nmi - fix incorrect NMI watchdog used by default

did not fix the problem completely, moreover it
introduced additional bug - nmi_watchdog would be
set to either NMI_LOCAL_APIC or NMI_IO_APIC
_regardless_ to boot option if being enabled thru
/proc/sys/kernel/nmi_watchdog. Sorry for that.
Fix it too.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: macro@linux-mips.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 8 insertions, 6 deletions

diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index cbd4fa3c475b..27ca8f69b466 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -487,14 +487,16 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file,
                 return -EIO;
         }
 
-#ifdef CONFIG_X86_64
         /* if nmi_watchdog is not set yet, then set it */
         nmi_watchdog_default();
-#else
-        if (lapic_watchdog_ok())
-                nmi_watchdog = NMI_LOCAL_APIC;
-        else
-                nmi_watchdog = NMI_IO_APIC;
+
+#ifdef CONFIG_X86_32
+        if (nmi_watchdog == NMI_NONE) {
+                if (lapic_watchdog_ok())
+                        nmi_watchdog = NMI_LOCAL_APIC;
+                else
+                        nmi_watchdog = NMI_IO_APIC;
+        }
 #endif
 
         if (nmi_watchdog == NMI_LOCAL_APIC) {