diff options
Diffstat (limited to 'arch/i386/kernel')
-rw-r--r-- | arch/i386/kernel/crash.c | 20 | ||||
-rw-r--r-- | arch/i386/kernel/nmi.c | 85 | ||||
-rw-r--r-- | arch/i386/kernel/traps.c | 23 |
3 files changed, 31 insertions, 97 deletions
diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c index 5b96f038367f..736c76d6b31d 100644 --- a/arch/i386/kernel/crash.c +++ b/arch/i386/kernel/crash.c @@ -22,6 +22,8 @@ #include <asm/nmi.h> #include <asm/hw_irq.h> #include <asm/apic.h> +#include <asm/kdebug.h> + #include <mach_ipi.h> @@ -93,9 +95,18 @@ static void crash_save_self(struct pt_regs *regs) #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) static atomic_t waiting_for_crash_ipi; -static int crash_nmi_callback(struct pt_regs *regs, int cpu) +static int crash_nmi_callback(struct notifier_block *self, + unsigned long val, void *data) { + struct pt_regs *regs; struct pt_regs fixed_regs; + int cpu; + + if (val != DIE_NMI) + return NOTIFY_OK; + + regs = ((struct die_args *)data)->regs; + cpu = raw_smp_processor_id(); /* Don't do anything if this handler is invoked on crashing cpu. * Otherwise, system will completely hang. Crashing cpu can get @@ -125,13 +136,18 @@ static void smp_send_nmi_allbutself(void) send_IPI_allbutself(NMI_VECTOR); } +static struct notifier_block crash_nmi_nb = { + .notifier_call = crash_nmi_callback, +}; + static void nmi_shootdown_cpus(void) { unsigned long msecs; atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); /* Would it be better to replace the trap vector here? */ - set_nmi_callback(crash_nmi_callback); + if (register_die_notifier(&crash_nmi_nb)) + return; /* return what? */ /* Ensure the new callback function is set before sending * out the NMI */ diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index bd96ea4f2942..acd3fdea2a21 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -42,20 +42,6 @@ static DEFINE_PER_CPU(unsigned long, evntsel_nmi_owner[3]); */ #define NMI_MAX_COUNTER_BITS 66 -/* - * lapic_nmi_owner tracks the ownership of the lapic NMI hardware: - * - it may be reserved by some other driver, or not - * - when not reserved by some other driver, it may be used for - * the NMI watchdog, or not - * - * This is maintained separately from nmi_active because the NMI - * watchdog may also be driven from the I/O APIC timer. - */ -static DEFINE_SPINLOCK(lapic_nmi_owner_lock); -static unsigned int lapic_nmi_owner; -#define LAPIC_NMI_WATCHDOG (1<<0) -#define LAPIC_NMI_RESERVED (1<<1) - /* nmi_active: * >0: the lapic NMI watchdog is active, but can be disabled * <0: the lapic NMI watchdog has not been set up, and cannot @@ -325,33 +311,6 @@ static void enable_lapic_nmi_watchdog(void) touch_nmi_watchdog(); } -int reserve_lapic_nmi(void) -{ - unsigned int old_owner; - - spin_lock(&lapic_nmi_owner_lock); - old_owner = lapic_nmi_owner; - lapic_nmi_owner |= LAPIC_NMI_RESERVED; - spin_unlock(&lapic_nmi_owner_lock); - if (old_owner & LAPIC_NMI_RESERVED) - return -EBUSY; - if (old_owner & LAPIC_NMI_WATCHDOG) - disable_lapic_nmi_watchdog(); - return 0; -} - -void release_lapic_nmi(void) -{ - unsigned int new_owner; - - spin_lock(&lapic_nmi_owner_lock); - new_owner = lapic_nmi_owner & ~LAPIC_NMI_RESERVED; - lapic_nmi_owner = new_owner; - spin_unlock(&lapic_nmi_owner_lock); - if (new_owner & LAPIC_NMI_WATCHDOG) - enable_lapic_nmi_watchdog(); -} - void disable_timer_nmi_watchdog(void) { BUG_ON(nmi_watchdog != NMI_IO_APIC); @@ -866,6 +825,15 @@ done: return rc; } +int do_nmi_callback(struct pt_regs * regs, int cpu) +{ +#ifdef CONFIG_SYSCTL + if (unknown_nmi_panic) + return unknown_nmi_panic_callback(regs, cpu); +#endif + return 0; +} + #ifdef CONFIG_SYSCTL static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) @@ -873,37 +841,8 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) unsigned char reason = get_nmi_reason(); char buf[64]; - if (!(reason & 0xc0)) { - sprintf(buf, "NMI received for unknown reason %02x\n", reason); - die_nmi(regs, buf); - } - return 0; -} - -/* - * proc handler for /proc/sys/kernel/unknown_nmi_panic - */ -int proc_unknown_nmi_panic(ctl_table *table, int write, struct file *file, - void __user *buffer, size_t *length, loff_t *ppos) -{ - int old_state; - - old_state = unknown_nmi_panic; - proc_dointvec(table, write, file, buffer, length, ppos); - if (!!old_state == !!unknown_nmi_panic) - return 0; - - if (unknown_nmi_panic) { - if (reserve_lapic_nmi() < 0) { - unknown_nmi_panic = 0; - return -EBUSY; - } else { - set_nmi_callback(unknown_nmi_panic_callback); - } - } else { - release_lapic_nmi(); - unset_nmi_callback(); - } + sprintf(buf, "NMI received for unknown reason %02x\n", reason); + die_nmi(regs, buf); return 0; } @@ -917,7 +856,5 @@ EXPORT_SYMBOL(reserve_perfctr_nmi); EXPORT_SYMBOL(release_perfctr_nmi); EXPORT_SYMBOL(reserve_evntsel_nmi); EXPORT_SYMBOL(release_evntsel_nmi); -EXPORT_SYMBOL(reserve_lapic_nmi); -EXPORT_SYMBOL(release_lapic_nmi); EXPORT_SYMBOL(disable_timer_nmi_watchdog); EXPORT_SYMBOL(enable_timer_nmi_watchdog); diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c index 282f0bd40dfd..7db664d0b25c 100644 --- a/arch/i386/kernel/traps.c +++ b/arch/i386/kernel/traps.c @@ -706,13 +706,6 @@ void die_nmi (struct pt_regs *regs, const char *msg) do_exit(SIGSEGV); } -static int dummy_nmi_callback(struct pt_regs * regs, int cpu) -{ - return 0; -} - -static nmi_callback_t nmi_callback = dummy_nmi_callback; - static void default_do_nmi(struct pt_regs * regs) { unsigned char reason = 0; @@ -732,9 +725,10 @@ static void default_do_nmi(struct pt_regs * regs) */ if (nmi_watchdog_tick(regs, reason)) return; + if (!do_nmi_callback(regs, smp_processor_id())) #endif - if (!rcu_dereference(nmi_callback)(regs, smp_processor_id())) unknown_nmi_error(reason, regs); + return; } if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP) @@ -765,19 +759,6 @@ fastcall void do_nmi(struct pt_regs * regs, long error_code) nmi_exit(); } -void set_nmi_callback(nmi_callback_t callback) -{ - vmalloc_sync_all(); - rcu_assign_pointer(nmi_callback, callback); -} -EXPORT_SYMBOL_GPL(set_nmi_callback); - -void unset_nmi_callback(void) -{ - nmi_callback = dummy_nmi_callback; -} -EXPORT_SYMBOL_GPL(unset_nmi_callback); - #ifdef CONFIG_KPROBES fastcall void __kprobes do_int3(struct pt_regs *regs, long error_code) { |