From 0328ecef9041fe477efc2404fd3aaa29e7ee0430 Mon Sep 17 00:00:00 2001 From: Daniel Gollub Date: Wed, 15 Aug 2007 02:40:35 +0200 Subject: [PATCH] x86_64: Fix to keep watchdog disabled by default for i386/x86_64 Fixed wrong expression which enabled watchdogs even if nmi_watchdog kernel parameter wasn't set. This regression got slightly introduced with commit b7471c6da94d30d3deadc55986cc38d1ff57f9ca. Introduced NMI_DISABLED (-1) which allows to switch the value of NMI_DEFAULT without breaking the APIC NMI watchdog code (again). Fixes: https://bugzilla.novell.com/show_bug.cgi?id=298084 http://bugzilla.kernel.org/show_bug.cgi?id=7839 And likely some more nmi_watchdog=0 related issues. Signed-off-by: Daniel Gollub Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- arch/i386/kernel/apic.c | 2 +- arch/i386/kernel/nmi.c | 4 ++-- arch/x86_64/kernel/nmi.c | 4 ++-- include/asm-i386/nmi.h | 3 ++- include/asm-x86_64/nmi.h | 3 ++- 5 files changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c index f9fff29e01a..3d67ae18d76 100644 --- a/arch/i386/kernel/apic.c +++ b/arch/i386/kernel/apic.c @@ -1085,7 +1085,7 @@ static int __init detect_init_APIC (void) if (l & MSR_IA32_APICBASE_ENABLE) mp_lapic_addr = l & MSR_IA32_APICBASE_BASE; - if (nmi_watchdog != NMI_NONE) + if (nmi_watchdog != NMI_NONE && nmi_watchdog != NMI_DISABLED) nmi_watchdog = NMI_LOCAL_APIC; printk(KERN_INFO "Found and enabled local APIC!\n"); diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index 99beac7f96c..8c1c965eb2a 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -77,7 +77,7 @@ static int __init check_nmi_watchdog(void) unsigned int *prev_nmi_count; int cpu; - if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DEFAULT)) + if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DISABLED)) return 0; if (!atomic_read(&nmi_active)) @@ -424,7 +424,7 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, if (!!old_state == !!nmi_watchdog_enabled) return 0; - if (atomic_read(&nmi_active) < 0) { + if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); return -EIO; } diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c index cb8ee9d02f8..0ec6d2ddb93 100644 --- a/arch/x86_64/kernel/nmi.c +++ b/arch/x86_64/kernel/nmi.c @@ -85,7 +85,7 @@ int __init check_nmi_watchdog (void) int *counts; int cpu; - if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DEFAULT)) + if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DISABLED)) return 0; if (!atomic_read(&nmi_active)) @@ -442,7 +442,7 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, if (!!old_state == !!nmi_watchdog_enabled) return 0; - if (atomic_read(&nmi_active) < 0) { + if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); return -EIO; } diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index ff30c98f87b..70a958a8e38 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -33,11 +33,12 @@ extern int nmi_watchdog_tick (struct pt_regs * regs, unsigned reason); extern atomic_t nmi_active; extern unsigned int nmi_watchdog; -#define NMI_DEFAULT -1 +#define NMI_DISABLED -1 #define NMI_NONE 0 #define NMI_IO_APIC 1 #define NMI_LOCAL_APIC 2 #define NMI_INVALID 3 +#define NMI_DEFAULT NMI_DISABLED struct ctl_table; struct file; diff --git a/include/asm-x86_64/nmi.h b/include/asm-x86_64/nmi.h index 5fb3c0de5cc..65b6acf3bb5 100644 --- a/include/asm-x86_64/nmi.h +++ b/include/asm-x86_64/nmi.h @@ -64,11 +64,12 @@ extern int setup_nmi_watchdog(char *); extern atomic_t nmi_active; extern unsigned int nmi_watchdog; -#define NMI_DEFAULT -1 +#define NMI_DISABLED -1 #define NMI_NONE 0 #define NMI_IO_APIC 1 #define NMI_LOCAL_APIC 2 #define NMI_INVALID 3 +#define NMI_DEFAULT NMI_DISABLED struct ctl_table; struct file; -- 2.41.0