diff options
Diffstat (limited to 'arch/i386/kernel/nmi.c')
-rw-r--r-- | arch/i386/kernel/nmi.c | 85 |
1 files changed, 11 insertions, 74 deletions
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]); | |||
42 | */ | 42 | */ |
43 | #define NMI_MAX_COUNTER_BITS 66 | 43 | #define NMI_MAX_COUNTER_BITS 66 |
44 | 44 | ||
45 | /* | ||
46 | * lapic_nmi_owner tracks the ownership of the lapic NMI hardware: | ||
47 | * - it may be reserved by some other driver, or not | ||
48 | * - when not reserved by some other driver, it may be used for | ||
49 | * the NMI watchdog, or not | ||
50 | * | ||
51 | * This is maintained separately from nmi_active because the NMI | ||
52 | * watchdog may also be driven from the I/O APIC timer. | ||
53 | */ | ||
54 | static DEFINE_SPINLOCK(lapic_nmi_owner_lock); | ||
55 | static unsigned int lapic_nmi_owner; | ||
56 | #define LAPIC_NMI_WATCHDOG (1<<0) | ||
57 | #define LAPIC_NMI_RESERVED (1<<1) | ||
58 | |||
59 | /* nmi_active: | 45 | /* nmi_active: |
60 | * >0: the lapic NMI watchdog is active, but can be disabled | 46 | * >0: the lapic NMI watchdog is active, but can be disabled |
61 | * <0: the lapic NMI watchdog has not been set up, and cannot | 47 | * <0: the lapic NMI watchdog has not been set up, and cannot |
@@ -325,33 +311,6 @@ static void enable_lapic_nmi_watchdog(void) | |||
325 | touch_nmi_watchdog(); | 311 | touch_nmi_watchdog(); |
326 | } | 312 | } |
327 | 313 | ||
328 | int reserve_lapic_nmi(void) | ||
329 | { | ||
330 | unsigned int old_owner; | ||
331 | |||
332 | spin_lock(&lapic_nmi_owner_lock); | ||
333 | old_owner = lapic_nmi_owner; | ||
334 | lapic_nmi_owner |= LAPIC_NMI_RESERVED; | ||
335 | spin_unlock(&lapic_nmi_owner_lock); | ||
336 | if (old_owner & LAPIC_NMI_RESERVED) | ||
337 | return -EBUSY; | ||
338 | if (old_owner & LAPIC_NMI_WATCHDOG) | ||
339 | disable_lapic_nmi_watchdog(); | ||
340 | return 0; | ||
341 | } | ||
342 | |||
343 | void release_lapic_nmi(void) | ||
344 | { | ||
345 | unsigned int new_owner; | ||
346 | |||
347 | spin_lock(&lapic_nmi_owner_lock); | ||
348 | new_owner = lapic_nmi_owner & ~LAPIC_NMI_RESERVED; | ||
349 | lapic_nmi_owner = new_owner; | ||
350 | spin_unlock(&lapic_nmi_owner_lock); | ||
351 | if (new_owner & LAPIC_NMI_WATCHDOG) | ||
352 | enable_lapic_nmi_watchdog(); | ||
353 | } | ||
354 | |||
355 | void disable_timer_nmi_watchdog(void) | 314 | void disable_timer_nmi_watchdog(void) |
356 | { | 315 | { |
357 | BUG_ON(nmi_watchdog != NMI_IO_APIC); | 316 | BUG_ON(nmi_watchdog != NMI_IO_APIC); |
@@ -866,6 +825,15 @@ done: | |||
866 | return rc; | 825 | return rc; |
867 | } | 826 | } |
868 | 827 | ||
828 | int do_nmi_callback(struct pt_regs * regs, int cpu) | ||
829 | { | ||
830 | #ifdef CONFIG_SYSCTL | ||
831 | if (unknown_nmi_panic) | ||
832 | return unknown_nmi_panic_callback(regs, cpu); | ||
833 | #endif | ||
834 | return 0; | ||
835 | } | ||
836 | |||
869 | #ifdef CONFIG_SYSCTL | 837 | #ifdef CONFIG_SYSCTL |
870 | 838 | ||
871 | static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) | 839 | 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) | |||
873 | unsigned char reason = get_nmi_reason(); | 841 | unsigned char reason = get_nmi_reason(); |
874 | char buf[64]; | 842 | char buf[64]; |
875 | 843 | ||
876 | if (!(reason & 0xc0)) { | 844 | sprintf(buf, "NMI received for unknown reason %02x\n", reason); |
877 | sprintf(buf, "NMI received for unknown reason %02x\n", reason); | 845 | die_nmi(regs, buf); |
878 | die_nmi(regs, buf); | ||
879 | } | ||
880 | return 0; | ||
881 | } | ||
882 | |||
883 | /* | ||
884 | * proc handler for /proc/sys/kernel/unknown_nmi_panic | ||
885 | */ | ||
886 | int proc_unknown_nmi_panic(ctl_table *table, int write, struct file *file, | ||
887 | void __user *buffer, size_t *length, loff_t *ppos) | ||
888 | { | ||
889 | int old_state; | ||
890 | |||
891 | old_state = unknown_nmi_panic; | ||
892 | proc_dointvec(table, write, file, buffer, length, ppos); | ||
893 | if (!!old_state == !!unknown_nmi_panic) | ||
894 | return 0; | ||
895 | |||
896 | if (unknown_nmi_panic) { | ||
897 | if (reserve_lapic_nmi() < 0) { | ||
898 | unknown_nmi_panic = 0; | ||
899 | return -EBUSY; | ||
900 | } else { | ||
901 | set_nmi_callback(unknown_nmi_panic_callback); | ||
902 | } | ||
903 | } else { | ||
904 | release_lapic_nmi(); | ||
905 | unset_nmi_callback(); | ||
906 | } | ||
907 | return 0; | 846 | return 0; |
908 | } | 847 | } |
909 | 848 | ||
@@ -917,7 +856,5 @@ EXPORT_SYMBOL(reserve_perfctr_nmi); | |||
917 | EXPORT_SYMBOL(release_perfctr_nmi); | 856 | EXPORT_SYMBOL(release_perfctr_nmi); |
918 | EXPORT_SYMBOL(reserve_evntsel_nmi); | 857 | EXPORT_SYMBOL(reserve_evntsel_nmi); |
919 | EXPORT_SYMBOL(release_evntsel_nmi); | 858 | EXPORT_SYMBOL(release_evntsel_nmi); |
920 | EXPORT_SYMBOL(reserve_lapic_nmi); | ||
921 | EXPORT_SYMBOL(release_lapic_nmi); | ||
922 | EXPORT_SYMBOL(disable_timer_nmi_watchdog); | 859 | EXPORT_SYMBOL(disable_timer_nmi_watchdog); |
923 | EXPORT_SYMBOL(enable_timer_nmi_watchdog); | 860 | EXPORT_SYMBOL(enable_timer_nmi_watchdog); |