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-rw-r--r--arch/x86/kernel/cpu/perf_event.c86
-rw-r--r--arch/x86/kernel/cpu/perf_event_amd.c175
-rw-r--r--arch/x86/kernel/cpu/perf_event_intel.c4
-rw-r--r--arch/x86/kernel/cpu/perf_event_p4.c8
-rw-r--r--arch/x86/kernel/cpu/perf_event_p6.c4
-rw-r--r--arch/x86/kernel/cpu/perfctr-watchdog.c4
-rw-r--r--arch/x86/kernel/dumpstack.c25
-rw-r--r--arch/x86/kernel/kgdb.c9
8 files changed, 234 insertions, 81 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 390fa6d8c140..ea03c725e465 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -300,7 +300,7 @@ x86_perf_event_update(struct perf_event *event)
*/
again:
prev_raw_count = local64_read(&hwc->prev_count);
- rdmsrl(hwc->event_base + idx, new_raw_count);
+ rdmsrl(hwc->event_base, new_raw_count);
if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
new_raw_count) != prev_raw_count)
@@ -323,6 +323,24 @@ again:
return new_raw_count;
}
+/* using X86_FEATURE_PERFCTR_CORE to later implement ALTERNATIVE() here */
+static inline int x86_pmu_addr_offset(int index)
+{
+ if (boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
+ return index << 1;
+ return index;
+}
+
+static inline unsigned int x86_pmu_config_addr(int index)
+{
+ return x86_pmu.eventsel + x86_pmu_addr_offset(index);
+}
+
+static inline unsigned int x86_pmu_event_addr(int index)
+{
+ return x86_pmu.perfctr + x86_pmu_addr_offset(index);
+}
+
static atomic_t active_events;
static DEFINE_MUTEX(pmc_reserve_mutex);
@@ -333,12 +351,12 @@ static bool reserve_pmc_hardware(void)
int i;
for (i = 0; i < x86_pmu.num_counters; i++) {
- if (!reserve_perfctr_nmi(x86_pmu.perfctr + i))
+ if (!reserve_perfctr_nmi(x86_pmu_event_addr(i)))
goto perfctr_fail;
}
for (i = 0; i < x86_pmu.num_counters; i++) {
- if (!reserve_evntsel_nmi(x86_pmu.eventsel + i))
+ if (!reserve_evntsel_nmi(x86_pmu_config_addr(i)))
goto eventsel_fail;
}
@@ -346,13 +364,13 @@ static bool reserve_pmc_hardware(void)
eventsel_fail:
for (i--; i >= 0; i--)
- release_evntsel_nmi(x86_pmu.eventsel + i);
+ release_evntsel_nmi(x86_pmu_config_addr(i));
i = x86_pmu.num_counters;
perfctr_fail:
for (i--; i >= 0; i--)
- release_perfctr_nmi(x86_pmu.perfctr + i);
+ release_perfctr_nmi(x86_pmu_event_addr(i));
return false;
}
@@ -362,8 +380,8 @@ static void release_pmc_hardware(void)
int i;
for (i = 0; i < x86_pmu.num_counters; i++) {
- release_perfctr_nmi(x86_pmu.perfctr + i);
- release_evntsel_nmi(x86_pmu.eventsel + i);
+ release_perfctr_nmi(x86_pmu_event_addr(i));
+ release_evntsel_nmi(x86_pmu_config_addr(i));
}
}
@@ -384,7 +402,7 @@ static bool check_hw_exists(void)
* complain and bail.
*/
for (i = 0; i < x86_pmu.num_counters; i++) {
- reg = x86_pmu.eventsel + i;
+ reg = x86_pmu_config_addr(i);
ret = rdmsrl_safe(reg, &val);
if (ret)
goto msr_fail;
@@ -409,8 +427,8 @@ static bool check_hw_exists(void)
* that don't trap on the MSR access and always return 0s.
*/
val = 0xabcdUL;
- ret = checking_wrmsrl(x86_pmu.perfctr, val);
- ret |= rdmsrl_safe(x86_pmu.perfctr, &val_new);
+ ret = checking_wrmsrl(x86_pmu_event_addr(0), val);
+ ret |= rdmsrl_safe(x86_pmu_event_addr(0), &val_new);
if (ret || val != val_new)
goto msr_fail;
@@ -619,11 +637,11 @@ static void x86_pmu_disable_all(void)
if (!test_bit(idx, cpuc->active_mask))
continue;
- rdmsrl(x86_pmu.eventsel + idx, val);
+ rdmsrl(x86_pmu_config_addr(idx), val);
if (!(val & ARCH_PERFMON_EVENTSEL_ENABLE))
continue;
val &= ~ARCH_PERFMON_EVENTSEL_ENABLE;
- wrmsrl(x86_pmu.eventsel + idx, val);
+ wrmsrl(x86_pmu_config_addr(idx), val);
}
}
@@ -644,21 +662,24 @@ static void x86_pmu_disable(struct pmu *pmu)
x86_pmu.disable_all();
}
+static inline void __x86_pmu_enable_event(struct hw_perf_event *hwc,
+ u64 enable_mask)
+{
+ wrmsrl(hwc->config_base, hwc->config | enable_mask);
+}
+
static void x86_pmu_enable_all(int added)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
int idx;
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
- struct perf_event *event = cpuc->events[idx];
- u64 val;
+ struct hw_perf_event *hwc = &cpuc->events[idx]->hw;
if (!test_bit(idx, cpuc->active_mask))
continue;
- val = event->hw.config;
- val |= ARCH_PERFMON_EVENTSEL_ENABLE;
- wrmsrl(x86_pmu.eventsel + idx, val);
+ __x86_pmu_enable_event(hwc, ARCH_PERFMON_EVENTSEL_ENABLE);
}
}
@@ -823,15 +844,10 @@ static inline void x86_assign_hw_event(struct perf_event *event,
hwc->event_base = 0;
} else if (hwc->idx >= X86_PMC_IDX_FIXED) {
hwc->config_base = MSR_ARCH_PERFMON_FIXED_CTR_CTRL;
- /*
- * We set it so that event_base + idx in wrmsr/rdmsr maps to
- * MSR_ARCH_PERFMON_FIXED_CTR0 ... CTR2:
- */
- hwc->event_base =
- MSR_ARCH_PERFMON_FIXED_CTR0 - X86_PMC_IDX_FIXED;
+ hwc->event_base = MSR_ARCH_PERFMON_FIXED_CTR0;
} else {
- hwc->config_base = x86_pmu.eventsel;
- hwc->event_base = x86_pmu.perfctr;
+ hwc->config_base = x86_pmu_config_addr(hwc->idx);
+ hwc->event_base = x86_pmu_event_addr(hwc->idx);
}
}
@@ -917,17 +933,11 @@ static void x86_pmu_enable(struct pmu *pmu)
x86_pmu.enable_all(added);
}
-static inline void __x86_pmu_enable_event(struct hw_perf_event *hwc,
- u64 enable_mask)
-{
- wrmsrl(hwc->config_base + hwc->idx, hwc->config | enable_mask);
-}
-
static inline void x86_pmu_disable_event(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
- wrmsrl(hwc->config_base + hwc->idx, hwc->config);
+ wrmsrl(hwc->config_base, hwc->config);
}
static DEFINE_PER_CPU(u64 [X86_PMC_IDX_MAX], pmc_prev_left);
@@ -980,7 +990,7 @@ x86_perf_event_set_period(struct perf_event *event)
*/
local64_set(&hwc->prev_count, (u64)-left);
- wrmsrl(hwc->event_base + idx, (u64)(-left) & x86_pmu.cntval_mask);
+ wrmsrl(hwc->event_base, (u64)(-left) & x86_pmu.cntval_mask);
/*
* Due to erratum on certan cpu we need
@@ -988,7 +998,7 @@ x86_perf_event_set_period(struct perf_event *event)
* is updated properly
*/
if (x86_pmu.perfctr_second_write) {
- wrmsrl(hwc->event_base + idx,
+ wrmsrl(hwc->event_base,
(u64)(-left) & x86_pmu.cntval_mask);
}
@@ -1115,8 +1125,8 @@ void perf_event_print_debug(void)
pr_info("CPU#%d: active: %016llx\n", cpu, *(u64 *)cpuc->active_mask);
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
- rdmsrl(x86_pmu.eventsel + idx, pmc_ctrl);
- rdmsrl(x86_pmu.perfctr + idx, pmc_count);
+ rdmsrl(x86_pmu_config_addr(idx), pmc_ctrl);
+ rdmsrl(x86_pmu_event_addr(idx), pmc_count);
prev_left = per_cpu(pmc_prev_left[idx], cpu);
@@ -1391,7 +1401,7 @@ static void __init pmu_check_apic(void)
pr_info("no hardware sampling interrupt available.\n");
}
-int __init init_hw_perf_events(void)
+static int __init init_hw_perf_events(void)
{
struct event_constraint *c;
int err;
@@ -1610,7 +1620,7 @@ out:
return ret;
}
-int x86_pmu_event_init(struct perf_event *event)
+static int x86_pmu_event_init(struct perf_event *event)
{
struct pmu *tmp;
int err;
diff --git a/arch/x86/kernel/cpu/perf_event_amd.c b/arch/x86/kernel/cpu/perf_event_amd.c
index 67e2202a6039..461f62bbd774 100644
--- a/arch/x86/kernel/cpu/perf_event_amd.c
+++ b/arch/x86/kernel/cpu/perf_event_amd.c
@@ -127,6 +127,11 @@ static int amd_pmu_hw_config(struct perf_event *event)
/*
* AMD64 events are detected based on their event codes.
*/
+static inline unsigned int amd_get_event_code(struct hw_perf_event *hwc)
+{
+ return ((hwc->config >> 24) & 0x0f00) | (hwc->config & 0x00ff);
+}
+
static inline int amd_is_nb_event(struct hw_perf_event *hwc)
{
return (hwc->config & 0xe0) == 0xe0;
@@ -385,13 +390,181 @@ static __initconst const struct x86_pmu amd_pmu = {
.cpu_dead = amd_pmu_cpu_dead,
};
+/* AMD Family 15h */
+
+#define AMD_EVENT_TYPE_MASK 0x000000F0ULL
+
+#define AMD_EVENT_FP 0x00000000ULL ... 0x00000010ULL
+#define AMD_EVENT_LS 0x00000020ULL ... 0x00000030ULL
+#define AMD_EVENT_DC 0x00000040ULL ... 0x00000050ULL
+#define AMD_EVENT_CU 0x00000060ULL ... 0x00000070ULL
+#define AMD_EVENT_IC_DE 0x00000080ULL ... 0x00000090ULL
+#define AMD_EVENT_EX_LS 0x000000C0ULL
+#define AMD_EVENT_DE 0x000000D0ULL
+#define AMD_EVENT_NB 0x000000E0ULL ... 0x000000F0ULL
+
+/*
+ * AMD family 15h event code/PMC mappings:
+ *
+ * type = event_code & 0x0F0:
+ *
+ * 0x000 FP PERF_CTL[5:3]
+ * 0x010 FP PERF_CTL[5:3]
+ * 0x020 LS PERF_CTL[5:0]
+ * 0x030 LS PERF_CTL[5:0]
+ * 0x040 DC PERF_CTL[5:0]
+ * 0x050 DC PERF_CTL[5:0]
+ * 0x060 CU PERF_CTL[2:0]
+ * 0x070 CU PERF_CTL[2:0]
+ * 0x080 IC/DE PERF_CTL[2:0]
+ * 0x090 IC/DE PERF_CTL[2:0]
+ * 0x0A0 ---
+ * 0x0B0 ---
+ * 0x0C0 EX/LS PERF_CTL[5:0]
+ * 0x0D0 DE PERF_CTL[2:0]
+ * 0x0E0 NB NB_PERF_CTL[3:0]
+ * 0x0F0 NB NB_PERF_CTL[3:0]
+ *
+ * Exceptions:
+ *
+ * 0x003 FP PERF_CTL[3]
+ * 0x00B FP PERF_CTL[3]
+ * 0x00D FP PERF_CTL[3]
+ * 0x023 DE PERF_CTL[2:0]
+ * 0x02D LS PERF_CTL[3]
+ * 0x02E LS PERF_CTL[3,0]
+ * 0x043 CU PERF_CTL[2:0]
+ * 0x045 CU PERF_CTL[2:0]
+ * 0x046 CU PERF_CTL[2:0]
+ * 0x054 CU PERF_CTL[2:0]
+ * 0x055 CU PERF_CTL[2:0]
+ * 0x08F IC PERF_CTL[0]
+ * 0x187 DE PERF_CTL[0]
+ * 0x188 DE PERF_CTL[0]
+ * 0x0DB EX PERF_CTL[5:0]
+ * 0x0DC LS PERF_CTL[5:0]
+ * 0x0DD LS PERF_CTL[5:0]
+ * 0x0DE LS PERF_CTL[5:0]
+ * 0x0DF LS PERF_CTL[5:0]
+ * 0x1D6 EX PERF_CTL[5:0]
+ * 0x1D8 EX PERF_CTL[5:0]
+ */
+
+static struct event_constraint amd_f15_PMC0 = EVENT_CONSTRAINT(0, 0x01, 0);
+static struct event_constraint amd_f15_PMC20 = EVENT_CONSTRAINT(0, 0x07, 0);
+static struct event_constraint amd_f15_PMC3 = EVENT_CONSTRAINT(0, 0x08, 0);
+static struct event_constraint amd_f15_PMC30 = EVENT_CONSTRAINT(0, 0x09, 0);
+static struct event_constraint amd_f15_PMC50 = EVENT_CONSTRAINT(0, 0x3F, 0);
+static struct event_constraint amd_f15_PMC53 = EVENT_CONSTRAINT(0, 0x38, 0);
+
+static struct event_constraint *
+amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, struct perf_event *event)
+{
+ unsigned int event_code = amd_get_event_code(&event->hw);
+
+ switch (event_code & AMD_EVENT_TYPE_MASK) {
+ case AMD_EVENT_FP:
+ switch (event_code) {
+ case 0x003:
+ case 0x00B:
+ case 0x00D:
+ return &amd_f15_PMC3;
+ default:
+ return &amd_f15_PMC53;
+ }
+ case AMD_EVENT_LS:
+ case AMD_EVENT_DC:
+ case AMD_EVENT_EX_LS:
+ switch (event_code) {
+ case 0x023:
+ case 0x043:
+ case 0x045:
+ case 0x046:
+ case 0x054:
+ case 0x055:
+ return &amd_f15_PMC20;
+ case 0x02D:
+ return &amd_f15_PMC3;
+ case 0x02E:
+ return &amd_f15_PMC30;
+ default:
+ return &amd_f15_PMC50;
+ }
+ case AMD_EVENT_CU:
+ case AMD_EVENT_IC_DE:
+ case AMD_EVENT_DE:
+ switch (event_code) {
+ case 0x08F:
+ case 0x187:
+ case 0x188:
+ return &amd_f15_PMC0;
+ case 0x0DB ... 0x0DF:
+ case 0x1D6:
+ case 0x1D8:
+ return &amd_f15_PMC50;
+ default:
+ return &amd_f15_PMC20;
+ }
+ case AMD_EVENT_NB:
+ /* not yet implemented */
+ return &emptyconstraint;
+ default:
+ return &emptyconstraint;
+ }
+}
+
+static __initconst const struct x86_pmu amd_pmu_f15h = {
+ .name = "AMD Family 15h",
+ .handle_irq = x86_pmu_handle_irq,
+ .disable_all = x86_pmu_disable_all,
+ .enable_all = x86_pmu_enable_all,
+ .enable = x86_pmu_enable_event,
+ .disable = x86_pmu_disable_event,
+ .hw_config = amd_pmu_hw_config,
+ .schedule_events = x86_schedule_events,
+ .eventsel = MSR_F15H_PERF_CTL,
+ .perfctr = MSR_F15H_PERF_CTR,
+ .event_map = amd_pmu_event_map,
+ .max_events = ARRAY_SIZE(amd_perfmon_event_map),
+ .num_counters = 6,
+ .cntval_bits = 48,
+ .cntval_mask = (1ULL << 48) - 1,
+ .apic = 1,
+ /* use highest bit to detect overflow */
+ .max_period = (1ULL << 47) - 1,
+ .get_event_constraints = amd_get_event_constraints_f15h,
+ /* nortbridge counters not yet implemented: */
+#if 0
+ .put_event_constraints = amd_put_event_constraints,
+
+ .cpu_prepare = amd_pmu_cpu_prepare,
+ .cpu_starting = amd_pmu_cpu_starting,
+ .cpu_dead = amd_pmu_cpu_dead,
+#endif
+};
+
static __init int amd_pmu_init(void)
{
/* Performance-monitoring supported from K7 and later: */
if (boot_cpu_data.x86 < 6)
return -ENODEV;
- x86_pmu = amd_pmu;
+ /*
+ * If core performance counter extensions exists, it must be
+ * family 15h, otherwise fail. See x86_pmu_addr_offset().
+ */
+ switch (boot_cpu_data.x86) {
+ case 0x15:
+ if (!cpu_has_perfctr_core)
+ return -ENODEV;
+ x86_pmu = amd_pmu_f15h;
+ break;
+ default:
+ if (cpu_has_perfctr_core)
+ return -ENODEV;
+ x86_pmu = amd_pmu;
+ break;
+ }
/* Events are common for all AMDs */
memcpy(hw_cache_event_ids, amd_hw_cache_event_ids,
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index d00f386b0b30..ba8aad157b87 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -804,8 +804,8 @@ static void intel_pmu_reset(void)
printk("clearing PMU state on CPU#%d\n", smp_processor_id());
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
- checking_wrmsrl(x86_pmu.eventsel + idx, 0ull);
- checking_wrmsrl(x86_pmu.perfctr + idx, 0ull);
+ checking_wrmsrl(x86_pmu_config_addr(idx), 0ull);
+ checking_wrmsrl(x86_pmu_event_addr(idx), 0ull);
}
for (idx = 0; idx < x86_pmu.num_counters_fixed; idx++)
checking_wrmsrl(MSR_ARCH_PERFMON_FIXED_CTR0 + idx, 0ull);
diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c
index ff751a9f182b..3769ac822f96 100644
--- a/arch/x86/kernel/cpu/perf_event_p4.c
+++ b/arch/x86/kernel/cpu/perf_event_p4.c
@@ -764,9 +764,9 @@ static inline int p4_pmu_clear_cccr_ovf(struct hw_perf_event *hwc)
u64 v;
/* an official way for overflow indication */
- rdmsrl(hwc->config_base + hwc->idx, v);
+ rdmsrl(hwc->config_base, v);
if (v & P4_CCCR_OVF) {
- wrmsrl(hwc->config_base + hwc->idx, v & ~P4_CCCR_OVF);
+ wrmsrl(hwc->config_base, v & ~P4_CCCR_OVF);
return 1;
}
@@ -815,7 +815,7 @@ static inline void p4_pmu_disable_event(struct perf_event *event)
* state we need to clear P4_CCCR_OVF, otherwise interrupt get
* asserted again and again
*/
- (void)checking_wrmsrl(hwc->config_base + hwc->idx,
+ (void)checking_wrmsrl(hwc->config_base,
(u64)(p4_config_unpack_cccr(hwc->config)) &
~P4_CCCR_ENABLE & ~P4_CCCR_OVF & ~P4_CCCR_RESERVED);
}
@@ -885,7 +885,7 @@ static void p4_pmu_enable_event(struct perf_event *event)
p4_pmu_enable_pebs(hwc->config);
(void)checking_wrmsrl(escr_addr, escr_conf);
- (void)checking_wrmsrl(hwc->config_base + hwc->idx,
+ (void)checking_wrmsrl(hwc->config_base,
(cccr & ~P4_CCCR_RESERVED) | P4_CCCR_ENABLE);
}
diff --git a/arch/x86/kernel/cpu/perf_event_p6.c b/arch/x86/kernel/cpu/perf_event_p6.c
index 34ba07be2cda..20c097e33860 100644
--- a/arch/x86/kernel/cpu/perf_event_p6.c
+++ b/arch/x86/kernel/cpu/perf_event_p6.c
@@ -68,7 +68,7 @@ p6_pmu_disable_event(struct perf_event *event)
if (cpuc->enabled)
val |= ARCH_PERFMON_EVENTSEL_ENABLE;
- (void)checking_wrmsrl(hwc->config_base + hwc->idx, val);
+ (void)checking_wrmsrl(hwc->config_base, val);
}
static void p6_pmu_enable_event(struct perf_event *event)
@@ -81,7 +81,7 @@ static void p6_pmu_enable_event(struct perf_event *event)
if (cpuc->enabled)
val |= ARCH_PERFMON_EVENTSEL_ENABLE;
- (void)checking_wrmsrl(hwc->config_base + hwc->idx, val);
+ (void)checking_wrmsrl(hwc->config_base, val);
}
static __initconst const struct x86_pmu p6_pmu = {
diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c
index d5a236615501..966512b2cacf 100644
--- a/arch/x86/kernel/cpu/perfctr-watchdog.c
+++ b/arch/x86/kernel/cpu/perfctr-watchdog.c
@@ -46,6 +46,8 @@ static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr)
/* returns the bit offset of the performance counter register */
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
+ if (msr >= MSR_F15H_PERF_CTR)
+ return (msr - MSR_F15H_PERF_CTR) >> 1;
return msr - MSR_K7_PERFCTR0;
case X86_VENDOR_INTEL:
if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
@@ -70,6 +72,8 @@ static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr)
/* returns the bit offset of the event selection register */
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
+ if (msr >= MSR_F15H_PERF_CTL)
+ return (msr - MSR_F15H_PERF_CTL) >> 1;
return msr - MSR_K7_EVNTSEL0;
case X86_VENDOR_INTEL:
if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index df20723a6a1b..220a1c11cfde 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -320,31 +320,6 @@ void die(const char *str, struct pt_regs *regs, long err)
oops_end(flags, regs, sig);
}
-void notrace __kprobes
-die_nmi(char *str, struct pt_regs *regs, int do_panic)
-{
- unsigned long flags;
-
- if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
- return;
-
- /*
- * We are in trouble anyway, lets at least try
- * to get a message out.
- */
- flags = oops_begin();
- printk(KERN_EMERG "%s", str);
- printk(" on CPU%d, ip %08lx, registers:\n",
- smp_processor_id(), regs->ip);
- show_registers(regs);
- oops_end(flags, regs, 0);
- if (do_panic || panic_on_oops)
- panic("Non maskable interrupt");
- nmi_exit();
- local_irq_enable();
- do_exit(SIGBUS);
-}
-
static int __init oops_setup(char *s)
{
if (!s)
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index a4130005028a..7c64c420a9f6 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -533,15 +533,6 @@ static int __kgdb_notify(struct die_args *args, unsigned long cmd)
}
return NOTIFY_DONE;
- case DIE_NMIWATCHDOG:
- if (atomic_read(&kgdb_active) != -1) {
- /* KGDB CPU roundup: */
- kgdb_nmicallback(raw_smp_processor_id(), regs);
- return NOTIFY_STOP;
- }
- /* Enter debugger: */
- break;
-
case DIE_DEBUG:
if (atomic_read(&kgdb_cpu_doing_single_step) != -1) {
if (user_mode(regs))