[PATCH] i386: Disable nmi watchdog on all ThinkPads

Even newer Thinkpads have bugs in SMM code that causes hangs with
NMI watchdog.

Signed-off-by: Andi Kleen <ak@suse.de>

1 files changed, 5 insertions, 5 deletions

diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c
index 3e8e3adb0489..eaafe233a5da 100644
--- a/arch/i386/kernel/nmi.c
+++ b/arch/i386/kernel/nmi.c
@@ -219,11 +219,11 @@ static int __init check_nmi_watchdog(void)
         int cpu;
 
         /* Enable NMI watchdog for newer systems.
-           Actually it should be safe for most systems before 2004 too except
-           for some IBM systems that corrupt registers when NMI happens
-           during SMM. Unfortunately we don't have more exact information
-           on these and use this coarse check. */
-        if (nmi_watchdog == NMI_DEFAULT && dmi_get_year(DMI_BIOS_DATE) >= 2004)
+           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))