diff options
| -rw-r--r-- | arch/i386/kernel/nmi.c | 52 | ||||
| -rw-r--r-- | arch/x86_64/kernel/nmi.c | 48 | ||||
| -rw-r--r-- | include/asm-i386/nmi.h | 1 | ||||
| -rw-r--r-- | include/asm-x86_64/nmi.h | 1 | ||||
| -rw-r--r-- | include/linux/sysctl.h | 1 | ||||
| -rw-r--r-- | kernel/sysctl.c | 11 |
6 files changed, 114 insertions, 0 deletions
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index acd3fdea2a2..28065d0b71a 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -846,6 +846,58 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) return 0; } +/* + * proc handler for /proc/sys/kernel/nmi_watchdog + */ +int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, + void __user *buffer, size_t *length, loff_t *ppos) +{ + int old_state; + + nmi_watchdog_enabled = (atomic_read(&nmi_active) > 0) ? 1 : 0; + old_state = nmi_watchdog_enabled; + proc_dointvec(table, write, file, buffer, length, ppos); + if (!!old_state == !!nmi_watchdog_enabled) + return 0; + + if (atomic_read(&nmi_active) < 0) { + printk(KERN_WARNING "NMI watchdog is permanently disabled\n"); + return -EINVAL; + } + + if (nmi_watchdog == NMI_DEFAULT) { + if (nmi_known_cpu() > 0) + nmi_watchdog = NMI_LOCAL_APIC; + else + nmi_watchdog = NMI_IO_APIC; + } + + if (nmi_watchdog == NMI_LOCAL_APIC) + { + if (nmi_watchdog_enabled) + enable_lapic_nmi_watchdog(); + else + disable_lapic_nmi_watchdog(); + } else if (nmi_watchdog == NMI_IO_APIC) { + /* FIXME + * for some reason these functions don't work + */ + printk("Can not enable/disable NMI on IO APIC\n"); + return -EINVAL; +#if 0 + if (nmi_watchdog_enabled) + enable_timer_nmi_watchdog(); + else + disable_timer_nmi_watchdog(); +#endif + } else { + printk( KERN_WARNING + "NMI watchdog doesn't know what hardware to touch\n"); + return -EIO; + } + return 0; +} + #endif EXPORT_SYMBOL(nmi_active); diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c index 9d175dcf3a2..3a17411a9a1 100644 --- a/arch/x86_64/kernel/nmi.c +++ b/arch/x86_64/kernel/nmi.c @@ -750,6 +750,54 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) return 0; } +/* + * proc handler for /proc/sys/kernel/nmi + */ +int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, + void __user *buffer, size_t *length, loff_t *ppos) +{ + int old_state; + + nmi_watchdog_enabled = (atomic_read(&nmi_active) > 0) ? 1 : 0; + old_state = nmi_watchdog_enabled; + proc_dointvec(table, write, file, buffer, length, ppos); + if (!!old_state == !!nmi_watchdog_enabled) + return 0; + + if (atomic_read(&nmi_active) < 0) { + printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); + return -EINVAL; + } + + /* if nmi_watchdog is not set yet, then set it */ + nmi_watchdog_default(); + + if (nmi_watchdog == NMI_LOCAL_APIC) + { + if (nmi_watchdog_enabled) + enable_lapic_nmi_watchdog(); + else + disable_lapic_nmi_watchdog(); + } else if (nmi_watchdog == NMI_IO_APIC) { + /* FIXME + * for some reason these functions don't work + */ + printk("Can not enable/disable NMI on IO APIC\n"); + return -EIO; +#if 0 + if (nmi_watchdog_enabled) + enable_timer_nmi_watchdog(); + else + disable_timer_nmi_watchdog(); +#endif + } else { + printk(KERN_WARNING + "NMI watchdog doesn't know what hardware to touch\n"); + return -EIO; + } + return 0; +} + #endif EXPORT_SYMBOL(nmi_active); diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index 34d6bf063b6..13b5d8311bf 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -14,6 +14,7 @@ */ int do_nmi_callback(struct pt_regs *regs, int cpu); +extern int nmi_watchdog_enabled; extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); extern int avail_to_resrv_perfctr_nmi(unsigned int); extern int reserve_perfctr_nmi(unsigned int); diff --git a/include/asm-x86_64/nmi.h b/include/asm-x86_64/nmi.h index 8818c39d34e..2c23b0df87d 100644 --- a/include/asm-x86_64/nmi.h +++ b/include/asm-x86_64/nmi.h @@ -43,6 +43,7 @@ extern void die_nmi(char *str, struct pt_regs *regs); extern int panic_on_timeout; extern int unknown_nmi_panic; +extern int nmi_watchdog_enabled; extern int check_nmi_watchdog(void); extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 736ed917a4f..ecb79ba52ae 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -150,6 +150,7 @@ enum KERN_IA64_UNALIGNED=72, /* int: ia64 unaligned userland trap enable */ KERN_COMPAT_LOG=73, /* int: print compat layer messages */ KERN_MAX_LOCK_DEPTH=74, + KERN_NMI_WATCHDOG=75, /* int: enable/disable nmi watchdog */ }; diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 83f16836162..040de6bd74d 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -76,6 +76,9 @@ extern int compat_log; #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) int unknown_nmi_panic; +int nmi_watchdog_enabled; +extern int proc_nmi_enabled(struct ctl_table *, int , struct file *, + void __user *, size_t *, loff_t *); #endif /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */ @@ -628,6 +631,14 @@ static ctl_table kern_table[] = { .mode = 0644, .proc_handler = &proc_dointvec, }, + { + .ctl_name = KERN_NMI_WATCHDOG, + .procname = "nmi_watchdog", + .data = &nmi_watchdog_enabled, + .maxlen = sizeof (int), + .mode = 0644, + .proc_handler = &proc_nmi_enabled, + }, #endif #if defined(CONFIG_X86) { |