Disable NMI watchdog by default properly

This reverts commit 6ebf622b2577c50b1f496bd6a5e8739e55ae7b1c and
replaces it with one that actually works.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c
index 821df34..1470242 100644 (file)
--- a/arch/i386/kernel/nmi.c
+++ b/arch/i386/kernel/nmi.c
@@ -245,14 +245,6 @@ static int __init check_nmi_watchdog(void)
        unsigned int *prev_nmi_count;
        int cpu;
 
-       /* Enable NMI watchdog for newer systems.
-          Probably safe on most older systems too, but let's be careful.
-          IBM ThinkPads use INT10 inside SMM and that allows early NMI inside SMM
-          which hangs the system. Disable watchdog for all thinkpads */
-       if (nmi_watchdog == NMI_DEFAULT && dmi_get_year(DMI_BIOS_DATE) >= 2004 &&
-               !dmi_name_in_vendors("ThinkPad"))
-               nmi_watchdog = NMI_LOCAL_APIC;
-
        if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DEFAULT))
                return 0;
 

diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c
index 486f4c6..82d9d85 100644 (file)
--- a/arch/x86_64/kernel/nmi.c
+++ b/arch/x86_64/kernel/nmi.c
@@ -187,10 +187,7 @@ void nmi_watchdog_default(void)
 {
        if (nmi_watchdog != NMI_DEFAULT)
                return;
-       if (nmi_known_cpu())
-               nmi_watchdog = NMI_LOCAL_APIC;
-       else
-               nmi_watchdog = NMI_IO_APIC;
+       nmi_watchdog = NMI_NONE;
 }
 
 static int endflag __initdata = 0;

diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h
index 64544cb..b04333e 100644 (file)
--- a/include/asm-i386/nmi.h
+++ b/include/asm-i386/nmi.h
@@ -33,7 +33,7 @@ extern int nmi_watchdog_tick (struct pt_regs * regs, unsigned reason);
 
 extern atomic_t nmi_active;
 extern unsigned int nmi_watchdog;
-#define NMI_DEFAULT     0
+#define NMI_DEFAULT     -1
 #define NMI_NONE       0
 #define NMI_IO_APIC    1
 #define NMI_LOCAL_APIC 2

diff --git a/include/asm-x86_64/nmi.h b/include/asm-x86_64/nmi.h
index ceb3d8d..72375e7 100644 (file)
--- a/include/asm-x86_64/nmi.h
+++ b/include/asm-x86_64/nmi.h
@@ -64,7 +64,7 @@ extern int setup_nmi_watchdog(char *);
 
 extern atomic_t nmi_active;
 extern unsigned int nmi_watchdog;
-#define NMI_DEFAULT    0
+#define NMI_DEFAULT    -1
 #define NMI_NONE       0
 #define NMI_IO_APIC    1
 #define NMI_LOCAL_APIC 2