From a1bae67243512ca30ceda48e3e24e25b543f8ab7 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Sat, 21 Oct 2006 18:37:02 +0200 Subject: [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 --- arch/i386/kernel/nmi.c | 10 +++++----- drivers/firmware/dmi_scan.c | 20 ++++++++++++++++++++ include/linux/dmi.h | 2 ++ 3 files changed, 27 insertions(+), 5 deletions(-) diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index 3e8e3adb048..eaafe233a5d 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)) diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index b8b596d5778..37deee6c0c1 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -326,6 +326,26 @@ char *dmi_get_system_info(int field) } EXPORT_SYMBOL(dmi_get_system_info); + +/** + * dmi_name_in_vendors - Check if string is anywhere in the DMI vendor information. + * @str: Case sensitive Name + */ +int dmi_name_in_vendors(char *str) +{ + static int fields[] = { DMI_BIOS_VENDOR, DMI_BIOS_VERSION, DMI_SYS_VENDOR, + DMI_PRODUCT_NAME, DMI_PRODUCT_VERSION, DMI_BOARD_VENDOR, + DMI_BOARD_NAME, DMI_BOARD_VERSION, DMI_NONE }; + int i; + for (i = 0; fields[i] != DMI_NONE; i++) { + int f = fields[i]; + if (dmi_ident[f] && strstr(dmi_ident[f], str)) + return 1; + } + return 0; +} +EXPORT_SYMBOL(dmi_name_in_vendors); + /** * dmi_find_device - find onboard device by type/name * @type: device type or %DMI_DEV_TYPE_ANY to match all device types diff --git a/include/linux/dmi.h b/include/linux/dmi.h index 38dc403be70..904bf3d2d90 100644 --- a/include/linux/dmi.h +++ b/include/linux/dmi.h @@ -69,6 +69,7 @@ extern struct dmi_device * dmi_find_device(int type, const char *name, struct dmi_device *from); extern void dmi_scan_machine(void); extern int dmi_get_year(int field); +extern int dmi_name_in_vendors(char *str); #else @@ -77,6 +78,7 @@ static inline char * dmi_get_system_info(int field) { return NULL; } static inline struct dmi_device * dmi_find_device(int type, const char *name, struct dmi_device *from) { return NULL; } static inline int dmi_get_year(int year) { return 0; } +static inline int dmi_name_in_vendors(char *s) { return 0; } #endif -- cgit v1.2.3