11 files changed, 79 insertions, 123 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 8e28bf2fc3ef..a135239badb7 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1025,7 +1025,8 @@ __setup("show_msr=", setup_show_msr);
 
 static __init int setup_noclflush(char *arg)
 {
-	setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
+	setup_clear_cpu_cap(X86_FEATURE_CLFLUSH);
+	setup_clear_cpu_cap(X86_FEATURE_CLFLUSHOPT);
 	return 1;
 }
 __setup("noclflush", setup_noclflush);
@@ -1078,6 +1079,10 @@ static __init int setup_disablecpuid(char *arg)
 }
 __setup("clearcpuid=", setup_disablecpuid);
 
+DEFINE_PER_CPU(unsigned long, kernel_stack) =
+	(unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
+EXPORT_PER_CPU_SYMBOL(kernel_stack);
+
 #ifdef CONFIG_X86_64
 struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table };
 struct desc_ptr debug_idt_descr = { NR_VECTORS * 16 - 1,
@@ -1094,10 +1099,6 @@ DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
 	&init_task;
 EXPORT_PER_CPU_SYMBOL(current_task);
 
-DEFINE_PER_CPU(unsigned long, kernel_stack) =
-	(unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
-EXPORT_PER_CPU_SYMBOL(kernel_stack);
-
 DEFINE_PER_CPU(char *, irq_stack_ptr) =
 	init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
 
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 897d6201ef10..a80029035bf2 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -274,10 +274,6 @@ static void intel_workarounds(struct cpuinfo_x86 *c)
 	}
 #endif
 
-#ifdef CONFIG_X86_NUMAQ
-	numaq_tsc_disable();
-#endif
-
 	intel_smp_check(c);
 }
 #else
diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index 0641113e2965..a952e9c85b6f 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -1225,21 +1225,24 @@ static struct notifier_block cacheinfo_cpu_notifier = {
 
 static int __init cache_sysfs_init(void)
 {
-	int i;
+	int i, err = 0;
 
 	if (num_cache_leaves == 0)
 		return 0;
 
+	cpu_notifier_register_begin();
 	for_each_online_cpu(i) {
-		int err;
 		struct device *dev = get_cpu_device(i);
 
 		err = cache_add_dev(dev);
 		if (err)
-			return err;
+			goto out;
 	}
-	register_hotcpu_notifier(&cacheinfo_cpu_notifier);
-	return 0;
+	__register_hotcpu_notifier(&cacheinfo_cpu_notifier);
+
+out:
+	cpu_notifier_register_done();
+	return err;
 }
 
 device_initcall(cache_sysfs_init);
diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c
index 36565373af87..afa9f0d487ea 100644
--- a/arch/x86/kernel/cpu/match.c
+++ b/arch/x86/kernel/cpu/match.c
@@ -47,45 +47,3 @@ const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match)
 	return NULL;
 }
 EXPORT_SYMBOL(x86_match_cpu);
-
-ssize_t arch_print_cpu_modalias(struct device *dev,
-				struct device_attribute *attr,
-				char *bufptr)
-{
-	int size = PAGE_SIZE;
-	int i, n;
-	char *buf = bufptr;
-
-	n = snprintf(buf, size, "x86cpu:vendor:%04X:family:%04X:"
-		     "model:%04X:feature:",
-		boot_cpu_data.x86_vendor,
-		boot_cpu_data.x86,
-		boot_cpu_data.x86_model);
-	size -= n;
-	buf += n;
-	size -= 1;
-	for (i = 0; i < NCAPINTS*32; i++) {
-		if (boot_cpu_has(i)) {
-			n = snprintf(buf, size, ",%04X", i);
-			if (n >= size) {
-				WARN(1, "x86 features overflow page\n");
-				break;
-			}
-			size -= n;
-			buf += n;
-		}
-	}
-	*buf++ = '\n';
-	return buf - bufptr;
-}
-
-int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
-	char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
-	if (buf) {
-		arch_print_cpu_modalias(NULL, NULL, buf);
-		add_uevent_var(env, "MODALIAS=%s", buf);
-		kfree(buf);
-	}
-	return 0;
-}
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 4d5419b249da..9b7734b1f975 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -2434,14 +2434,18 @@ static __init int mcheck_init_device(void)
 	if (err)
 		return err;
 
+	cpu_notifier_register_begin();
 	for_each_online_cpu(i) {
 		err = mce_device_create(i);
-		if (err)
+		if (err) {
+			cpu_notifier_register_done();
 			return err;
+		}
 	}
 
 	register_syscore_ops(&mce_syscore_ops);
-	register_hotcpu_notifier(&mce_cpu_notifier);
+	__register_hotcpu_notifier(&mce_cpu_notifier);
+	cpu_notifier_register_done();
 
 	/* register character device /dev/mcelog */
 	misc_register(&mce_chrdev_device);
diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c
index 3eec7de76efb..d921b7ee6595 100644
--- a/arch/x86/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c
@@ -271,9 +271,6 @@ static void thermal_throttle_remove_dev(struct device *dev)
 	sysfs_remove_group(&dev->kobj, &thermal_attr_group);
 }
 
-/* Mutex protecting device creation against CPU hotplug: */
-static DEFINE_MUTEX(therm_cpu_lock);
-
 /* Get notified when a cpu comes on/off. Be hotplug friendly. */
 static int
 thermal_throttle_cpu_callback(struct notifier_block *nfb,
@@ -289,18 +286,14 @@ thermal_throttle_cpu_callback(struct notifier_block *nfb,
 	switch (action) {
 	case CPU_UP_PREPARE:
 	case CPU_UP_PREPARE_FROZEN:
-		mutex_lock(&therm_cpu_lock);
 		err = thermal_throttle_add_dev(dev, cpu);
-		mutex_unlock(&therm_cpu_lock);
 		WARN_ON(err);
 		break;
 	case CPU_UP_CANCELED:
 	case CPU_UP_CANCELED_FROZEN:
 	case CPU_DEAD:
 	case CPU_DEAD_FROZEN:
-		mutex_lock(&therm_cpu_lock);
 		thermal_throttle_remove_dev(dev);
-		mutex_unlock(&therm_cpu_lock);
 		break;
 	}
 	return notifier_from_errno(err);
@@ -319,19 +312,16 @@ static __init int thermal_throttle_init_device(void)
 	if (!atomic_read(&therm_throt_en))
 		return 0;
 
-	register_hotcpu_notifier(&thermal_throttle_cpu_notifier);
+	cpu_notifier_register_begin();
 
-#ifdef CONFIG_HOTPLUG_CPU
-	mutex_lock(&therm_cpu_lock);
-#endif
 	/* connect live CPUs to sysfs */
 	for_each_online_cpu(cpu) {
 		err = thermal_throttle_add_dev(get_cpu_device(cpu), cpu);
 		WARN_ON(err);
 	}
-#ifdef CONFIG_HOTPLUG_CPU
-	mutex_unlock(&therm_cpu_lock);
-#endif
+
+	__register_hotcpu_notifier(&thermal_throttle_cpu_notifier);
+	cpu_notifier_register_done();
 
 	return 0;
 }
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 832d05a914ba..76f98fe5b35c 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -17,6 +17,7 @@
 #include <linux/hardirq.h>
 #include <linux/efi.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <asm/processor.h>
 #include <asm/hypervisor.h>
 #include <asm/hyperv.h>
@@ -31,6 +32,45 @@
 struct ms_hyperv_info ms_hyperv;
 EXPORT_SYMBOL_GPL(ms_hyperv);
 
+#if IS_ENABLED(CONFIG_HYPERV)
+static void (*vmbus_handler)(void);
+
+void hyperv_vector_handler(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	irq_enter();
+	exit_idle();
+
+	inc_irq_stat(irq_hv_callback_count);
+	if (vmbus_handler)
+		vmbus_handler();
+
+	irq_exit();
+	set_irq_regs(old_regs);
+}
+
+void hv_setup_vmbus_irq(void (*handler)(void))
+{
+	vmbus_handler = handler;
+	/*
+	 * Setup the IDT for hypervisor callback. Prevent reallocation
+	 * at module reload.
+	 */
+	if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors))
+		alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR,
+				hyperv_callback_vector);
+}
+
+void hv_remove_vmbus_irq(void)
+{
+	/* We have no way to deallocate the interrupt gate */
+	vmbus_handler = NULL;
+}
+EXPORT_SYMBOL_GPL(hv_setup_vmbus_irq);
+EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq);
+#endif
+
 static uint32_t  __init ms_hyperv_platform(void)
 {
 	u32 eax;
@@ -119,41 +159,3 @@ const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = {
 	.init_platform		= ms_hyperv_init_platform,
 };
 EXPORT_SYMBOL(x86_hyper_ms_hyperv);
-
-#if IS_ENABLED(CONFIG_HYPERV)
-static int vmbus_irq = -1;
-static irq_handler_t vmbus_isr;
-
-void hv_register_vmbus_handler(int irq, irq_handler_t handler)
-{
-	/*
-	 * Setup the IDT for hypervisor callback.
-	 */
-	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, hyperv_callback_vector);
-
-	vmbus_irq = irq;
-	vmbus_isr = handler;
-}
-
-void hyperv_vector_handler(struct pt_regs *regs)
-{
-	struct pt_regs *old_regs = set_irq_regs(regs);
-	struct irq_desc *desc;
-
-	irq_enter();
-	exit_idle();
-
-	desc = irq_to_desc(vmbus_irq);
-
-	if (desc)
-		generic_handle_irq_desc(vmbus_irq, desc);
-
-	irq_exit();
-	set_irq_regs(old_regs);
-}
-#else
-void hv_register_vmbus_handler(int irq, irq_handler_t handler)
-{
-}
-#endif
-EXPORT_SYMBOL_GPL(hv_register_vmbus_handler);
diff --git a/arch/x86/kernel/cpu/perf_event_amd_ibs.c b/arch/x86/kernel/cpu/perf_event_amd_ibs.c
index 4b8e4d3cd6ea..4c36bbe3173a 100644
--- a/arch/x86/kernel/cpu/perf_event_amd_ibs.c
+++ b/arch/x86/kernel/cpu/perf_event_amd_ibs.c
@@ -926,13 +926,13 @@ static __init int amd_ibs_init(void)
 		goto out;
 
 	perf_ibs_pm_init();
-	get_online_cpus();
+	cpu_notifier_register_begin();
 	ibs_caps = caps;
 	/* make ibs_caps visible to other cpus: */
 	smp_mb();
-	perf_cpu_notifier(perf_ibs_cpu_notifier);
 	smp_call_function(setup_APIC_ibs, NULL, 1);
-	put_online_cpus();
+	__perf_cpu_notifier(perf_ibs_cpu_notifier);
+	cpu_notifier_register_done();
 
 	ret = perf_event_ibs_init();
 out:
diff --git a/arch/x86/kernel/cpu/perf_event_amd_uncore.c b/arch/x86/kernel/cpu/perf_event_amd_uncore.c
index 754291adec33..3bbdf4cd38b9 100644
--- a/arch/x86/kernel/cpu/perf_event_amd_uncore.c
+++ b/arch/x86/kernel/cpu/perf_event_amd_uncore.c
@@ -531,15 +531,16 @@ static int __init amd_uncore_init(void)
 	if (ret)
 		return -ENODEV;
 
-	get_online_cpus();
+	cpu_notifier_register_begin();
+
 	/* init cpus already online before registering for hotplug notifier */
 	for_each_online_cpu(cpu) {
 		amd_uncore_cpu_up_prepare(cpu);
 		smp_call_function_single(cpu, init_cpu_already_online, NULL, 1);
 	}
 
-	register_cpu_notifier(&amd_uncore_cpu_notifier_block);
-	put_online_cpus();
+	__register_cpu_notifier(&amd_uncore_cpu_notifier_block);
+	cpu_notifier_register_done();
 
 	return 0;
 }
diff --git a/arch/x86/kernel/cpu/perf_event_intel_rapl.c b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
index 5ad35ad94d0f..059218ed5208 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_rapl.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
@@ -646,19 +646,20 @@ static int __init rapl_pmu_init(void)
 		/* unsupported */
 		return 0;
 	}
-	get_online_cpus();
+
+	cpu_notifier_register_begin();
 
 	for_each_online_cpu(cpu) {
 		rapl_cpu_prepare(cpu);
 		rapl_cpu_init(cpu);
 	}
 
-	perf_cpu_notifier(rapl_cpu_notifier);
+	__perf_cpu_notifier(rapl_cpu_notifier);
 
 	ret = perf_pmu_register(&rapl_pmu_class, "power", -1);
 	if (WARN_ON(ret)) {
 		pr_info("RAPL PMU detected, registration failed (%d), RAPL PMU disabled\n", ret);
-		put_online_cpus();
+		cpu_notifier_register_done();
 		return -1;
 	}
 
@@ -672,7 +673,7 @@ static int __init rapl_pmu_init(void)
 		hweight32(rapl_cntr_mask),
 		ktime_to_ms(pmu->timer_interval));
 
-	put_online_cpus();
+	cpu_notifier_register_done();
 
 	return 0;
 }
diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
index bd2253d40cff..65bbbea38b9c 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
@@ -4244,7 +4244,7 @@ static void __init uncore_cpumask_init(void)
 	if (!cpumask_empty(&uncore_cpu_mask))
 		return;
 
-	get_online_cpus();
+	cpu_notifier_register_begin();
 
 	for_each_online_cpu(cpu) {
 		int i, phys_id = topology_physical_package_id(cpu);
@@ -4263,9 +4263,9 @@ static void __init uncore_cpumask_init(void)
 	}
 	on_each_cpu(uncore_cpu_setup, NULL, 1);
 
-	register_cpu_notifier(&uncore_cpu_nb);
+	__register_cpu_notifier(&uncore_cpu_nb);
 
-	put_online_cpus();
+	cpu_notifier_register_done();
 }