diff options
| -rw-r--r-- | drivers/kvm/kvm.h | 1 | ||||
| -rw-r--r-- | drivers/kvm/kvm_main.c | 64 | ||||
| -rw-r--r-- | drivers/kvm/svm.c | 5 | ||||
| -rw-r--r-- | drivers/kvm/vmx.c | 8 |
4 files changed, 77 insertions, 1 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index c48cebf8511d..04574a9d4430 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -341,6 +341,7 @@ struct kvm_arch_ops { struct kvm_vcpu *(*vcpu_load)(struct kvm_vcpu *vcpu); void (*vcpu_put)(struct kvm_vcpu *vcpu); + void (*vcpu_decache)(struct kvm_vcpu *vcpu); int (*set_guest_debug)(struct kvm_vcpu *vcpu, struct kvm_debug_guest *dbg); diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index a6cd1c1fe29a..291d298868fc 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -34,6 +34,7 @@ #include <linux/highmem.h> #include <linux/file.h> #include <asm/desc.h> +#include <linux/cpu.h> #include "x86_emulate.h" #include "segment_descriptor.h" @@ -2039,6 +2040,64 @@ static struct notifier_block kvm_reboot_notifier = { .priority = 0, }; +/* + * Make sure that a cpu that is being hot-unplugged does not have any vcpus + * cached on it. + */ +static void decache_vcpus_on_cpu(int cpu) +{ + struct kvm *vm; + struct kvm_vcpu *vcpu; + int i; + + spin_lock(&kvm_lock); + list_for_each_entry(vm, &vm_list, vm_list) + for (i = 0; i < KVM_MAX_VCPUS; ++i) { + vcpu = &vm->vcpus[i]; + /* + * If the vcpu is locked, then it is running on some + * other cpu and therefore it is not cached on the + * cpu in question. + * + * If it's not locked, check the last cpu it executed + * on. + */ + if (mutex_trylock(&vcpu->mutex)) { + if (vcpu->cpu == cpu) { + kvm_arch_ops->vcpu_decache(vcpu); + vcpu->cpu = -1; + } + mutex_unlock(&vcpu->mutex); + } + } + spin_unlock(&kvm_lock); +} + +static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val, + void *v) +{ + int cpu = (long)v; + + switch (val) { + case CPU_DEAD: + case CPU_UP_CANCELED: + decache_vcpus_on_cpu(cpu); + smp_call_function_single(cpu, kvm_arch_ops->hardware_disable, + NULL, 0, 1); + break; + case CPU_UP_PREPARE: + smp_call_function_single(cpu, kvm_arch_ops->hardware_enable, + NULL, 0, 1); + break; + } + return NOTIFY_OK; +} + +static struct notifier_block kvm_cpu_notifier = { + .notifier_call = kvm_cpu_hotplug, + .priority = 20, /* must be > scheduler priority */ +}; + static __init void kvm_init_debug(void) { struct kvm_stats_debugfs_item *p; @@ -2085,6 +2144,9 @@ int kvm_init_arch(struct kvm_arch_ops *ops, struct module *module) return r; on_each_cpu(kvm_arch_ops->hardware_enable, NULL, 0, 1); + r = register_cpu_notifier(&kvm_cpu_notifier); + if (r) + goto out_free_1; register_reboot_notifier(&kvm_reboot_notifier); kvm_chardev_ops.owner = module; @@ -2099,6 +2161,8 @@ int kvm_init_arch(struct kvm_arch_ops *ops, struct module *module) out_free: unregister_reboot_notifier(&kvm_reboot_notifier); + unregister_cpu_notifier(&kvm_cpu_notifier); +out_free_1: on_each_cpu(kvm_arch_ops->hardware_disable, NULL, 0, 1); kvm_arch_ops->hardware_unsetup(); return r; diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c index 4fa50bd0dceb..83da4ea150a3 100644 --- a/drivers/kvm/svm.c +++ b/drivers/kvm/svm.c @@ -609,6 +609,10 @@ static void svm_vcpu_put(struct kvm_vcpu *vcpu) put_cpu(); } +static void svm_vcpu_decache(struct kvm_vcpu *vcpu) +{ +} + static void svm_cache_regs(struct kvm_vcpu *vcpu) { vcpu->regs[VCPU_REGS_RAX] = vcpu->svm->vmcb->save.rax; @@ -1677,6 +1681,7 @@ static struct kvm_arch_ops svm_arch_ops = { .vcpu_load = svm_vcpu_load, .vcpu_put = svm_vcpu_put, + .vcpu_decache = svm_vcpu_decache, .set_guest_debug = svm_guest_debug, .get_msr = svm_get_msr, diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index 28da0cae64a7..1e640b899175 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -250,6 +250,11 @@ static void vmx_vcpu_put(struct kvm_vcpu *vcpu) put_cpu(); } +static void vmx_vcpu_decache(struct kvm_vcpu *vcpu) +{ + vcpu_clear(vcpu); +} + static unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu) { return vmcs_readl(GUEST_RFLAGS); @@ -509,7 +514,7 @@ static __init int vmx_disabled_by_bios(void) return (msr & 5) == 1; /* locked but not enabled */ } -static __init void hardware_enable(void *garbage) +static void hardware_enable(void *garbage) { int cpu = raw_smp_processor_id(); u64 phys_addr = __pa(per_cpu(vmxarea, cpu)); @@ -2023,6 +2028,7 @@ static struct kvm_arch_ops vmx_arch_ops = { .vcpu_load = vmx_vcpu_load, .vcpu_put = vmx_vcpu_put, + .vcpu_decache = vmx_vcpu_decache, .set_guest_debug = set_guest_debug, .get_msr = vmx_get_msr, |