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-rw-r--r--arch/x86/kernel/apic/apic.c17
-rw-r--r--arch/x86/kernel/cpu/hypervisor.c3
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce.c4
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce_amd.c22
-rw-r--r--arch/x86/kernel/kvm.c64
-rw-r--r--arch/x86/kernel/module.c2
6 files changed, 104 insertions, 8 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index c421512ca5e..98e24131ff3 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2143,6 +2143,23 @@ int default_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
}
/*
+ * Override the generic EOI implementation with an optimized version.
+ * Only called during early boot when only one CPU is active and with
+ * interrupts disabled, so we know this does not race with actual APIC driver
+ * use.
+ */
+void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
+{
+ struct apic **drv;
+
+ for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
+ /* Should happen once for each apic */
+ WARN_ON((*drv)->eoi_write == eoi_write);
+ (*drv)->eoi_write = eoi_write;
+ }
+}
+
+/*
* Power management
*/
#ifdef CONFIG_PM
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
index 755f64fb074..a8f8fa9769d 100644
--- a/arch/x86/kernel/cpu/hypervisor.c
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -37,6 +37,9 @@ static const __initconst struct hypervisor_x86 * const hypervisors[] =
#endif
&x86_hyper_vmware,
&x86_hyper_ms_hyperv,
+#ifdef CONFIG_KVM_GUEST
+ &x86_hyper_kvm,
+#endif
};
const struct hypervisor_x86 *x86_hyper;
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 9473e8772fd..5e095f873e3 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -60,8 +60,6 @@ static DEFINE_MUTEX(mce_chrdev_read_mutex);
int mce_disabled __read_mostly;
-#define MISC_MCELOG_MINOR 227
-
#define SPINUNIT 100 /* 100ns */
atomic_t mce_entry;
@@ -2346,7 +2344,7 @@ static __init int mcheck_init_device(void)
return err;
}
-device_initcall(mcheck_init_device);
+device_initcall_sync(mcheck_init_device);
/*
* Old style boot options parsing. Only for compatibility.
diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index 671b95a2ffb..c4e916d7737 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -759,4 +759,24 @@ static __init int threshold_init_device(void)
return 0;
}
-device_initcall(threshold_init_device);
+/*
+ * there are 3 funcs which need to be _initcalled in a logic sequence:
+ * 1. xen_late_init_mcelog
+ * 2. mcheck_init_device
+ * 3. threshold_init_device
+ *
+ * xen_late_init_mcelog must register xen_mce_chrdev_device before
+ * native mce_chrdev_device registration if running under xen platform;
+ *
+ * mcheck_init_device should be inited before threshold_init_device to
+ * initialize mce_device, otherwise a NULL ptr dereference will cause panic.
+ *
+ * so we use following _initcalls
+ * 1. device_initcall(xen_late_init_mcelog);
+ * 2. device_initcall_sync(mcheck_init_device);
+ * 3. late_initcall(threshold_init_device);
+ *
+ * when running under xen, the initcall order is 1,2,3;
+ * on baremetal, we skip 1 and we do only 2 and 3.
+ */
+late_initcall(threshold_init_device);
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index e554e5ad2fe..c1d61ee4b4f 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -39,6 +39,9 @@
#include <asm/desc.h>
#include <asm/tlbflush.h>
#include <asm/idle.h>
+#include <asm/apic.h>
+#include <asm/apicdef.h>
+#include <asm/hypervisor.h>
static int kvmapf = 1;
@@ -283,6 +286,22 @@ static void kvm_register_steal_time(void)
cpu, __pa(st));
}
+static DEFINE_PER_CPU(unsigned long, kvm_apic_eoi) = KVM_PV_EOI_DISABLED;
+
+static void kvm_guest_apic_eoi_write(u32 reg, u32 val)
+{
+ /**
+ * This relies on __test_and_clear_bit to modify the memory
+ * in a way that is atomic with respect to the local CPU.
+ * The hypervisor only accesses this memory from the local CPU so
+ * there's no need for lock or memory barriers.
+ * An optimization barrier is implied in apic write.
+ */
+ if (__test_and_clear_bit(KVM_PV_EOI_BIT, &__get_cpu_var(kvm_apic_eoi)))
+ return;
+ apic_write(APIC_EOI, APIC_EOI_ACK);
+}
+
void __cpuinit kvm_guest_cpu_init(void)
{
if (!kvm_para_available())
@@ -300,11 +319,20 @@ void __cpuinit kvm_guest_cpu_init(void)
smp_processor_id());
}
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) {
+ unsigned long pa;
+ /* Size alignment is implied but just to make it explicit. */
+ BUILD_BUG_ON(__alignof__(kvm_apic_eoi) < 4);
+ __get_cpu_var(kvm_apic_eoi) = 0;
+ pa = __pa(&__get_cpu_var(kvm_apic_eoi)) | KVM_MSR_ENABLED;
+ wrmsrl(MSR_KVM_PV_EOI_EN, pa);
+ }
+
if (has_steal_clock)
kvm_register_steal_time();
}
-static void kvm_pv_disable_apf(void *unused)
+static void kvm_pv_disable_apf(void)
{
if (!__get_cpu_var(apf_reason).enabled)
return;
@@ -316,11 +344,23 @@ static void kvm_pv_disable_apf(void *unused)
smp_processor_id());
}
+static void kvm_pv_guest_cpu_reboot(void *unused)
+{
+ /*
+ * We disable PV EOI before we load a new kernel by kexec,
+ * since MSR_KVM_PV_EOI_EN stores a pointer into old kernel's memory.
+ * New kernel can re-enable when it boots.
+ */
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
+ wrmsrl(MSR_KVM_PV_EOI_EN, 0);
+ kvm_pv_disable_apf();
+}
+
static int kvm_pv_reboot_notify(struct notifier_block *nb,
unsigned long code, void *unused)
{
if (code == SYS_RESTART)
- on_each_cpu(kvm_pv_disable_apf, NULL, 1);
+ on_each_cpu(kvm_pv_guest_cpu_reboot, NULL, 1);
return NOTIFY_DONE;
}
@@ -371,7 +411,9 @@ static void __cpuinit kvm_guest_cpu_online(void *dummy)
static void kvm_guest_cpu_offline(void *dummy)
{
kvm_disable_steal_time();
- kvm_pv_disable_apf(NULL);
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
+ wrmsrl(MSR_KVM_PV_EOI_EN, 0);
+ kvm_pv_disable_apf();
apf_task_wake_all();
}
@@ -424,6 +466,9 @@ void __init kvm_guest_init(void)
pv_time_ops.steal_clock = kvm_steal_clock;
}
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
+ apic_set_eoi_write(kvm_guest_apic_eoi_write);
+
#ifdef CONFIG_SMP
smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu;
register_cpu_notifier(&kvm_cpu_notifier);
@@ -432,6 +477,19 @@ void __init kvm_guest_init(void)
#endif
}
+static bool __init kvm_detect(void)
+{
+ if (!kvm_para_available())
+ return false;
+ return true;
+}
+
+const struct hypervisor_x86 x86_hyper_kvm __refconst = {
+ .name = "KVM",
+ .detect = kvm_detect,
+};
+EXPORT_SYMBOL_GPL(x86_hyper_kvm);
+
static __init int activate_jump_labels(void)
{
if (has_steal_clock) {
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 202494d2ec6..216a4d754b0 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -81,7 +81,7 @@ int apply_relocate(Elf32_Shdr *sechdrs,
*location += sym->st_value;
break;
case R_386_PC32:
- /* Add the value, subtract its postition */
+ /* Add the value, subtract its position */
*location += sym->st_value - (uint32_t)location;
break;
default: