diff options
Diffstat (limited to 'arch/x86/kernel/kvm.c')
| -rw-r--r-- | arch/x86/kernel/kvm.c | 107 |
1 files changed, 83 insertions, 24 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index e820568ed4d5..f582dda8dd34 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -24,6 +24,7 @@ #include <linux/debugfs.h> #include <linux/nmi.h> #include <linux/swait.h> +#include <linux/syscore_ops.h> #include <asm/timer.h> #include <asm/cpu.h> #include <asm/traps.h> @@ -33,6 +34,7 @@ #include <asm/apicdef.h> #include <asm/hypervisor.h> #include <asm/tlb.h> +#include <asm/reboot.h> static int kvmapf = 1; @@ -57,6 +59,7 @@ static DEFINE_PER_CPU_DECRYPTED(struct kvm_vcpu_pv_apf_data, apf_reason) __align DEFINE_PER_CPU_DECRYPTED(struct kvm_steal_time, steal_time) __aligned(64) __visible; static int has_steal_clock = 0; +static int has_guest_poll = 0; /* * No need for any "IO delay" on KVM */ @@ -351,6 +354,14 @@ static void kvm_pv_disable_apf(void) smp_processor_id()); } +static void kvm_disable_steal_time(void) +{ + if (!has_steal_clock) + return; + + wrmsr(MSR_KVM_STEAL_TIME, 0, 0); +} + static void kvm_pv_guest_cpu_reboot(void *unused) { /* @@ -393,14 +404,6 @@ static u64 kvm_steal_clock(int cpu) return steal; } -void kvm_disable_steal_time(void) -{ - if (!has_steal_clock) - return; - - wrmsr(MSR_KVM_STEAL_TIME, 0, 0); -} - static inline void __set_percpu_decrypted(void *ptr, unsigned long size) { early_set_memory_decrypted((unsigned long) ptr, size); @@ -428,6 +431,27 @@ static void __init sev_map_percpu_data(void) } } +static void kvm_guest_cpu_offline(bool shutdown) +{ + kvm_disable_steal_time(); + if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) + wrmsrl(MSR_KVM_PV_EOI_EN, 0); + kvm_pv_disable_apf(); + if (!shutdown) + apf_task_wake_all(); + kvmclock_disable(); +} + +static int kvm_cpu_online(unsigned int cpu) +{ + unsigned long flags; + + local_irq_save(flags); + kvm_guest_cpu_init(); + local_irq_restore(flags); + return 0; +} + #ifdef CONFIG_SMP #define KVM_IPI_CLUSTER_SIZE (2 * BITS_PER_LONG) @@ -464,7 +488,7 @@ static void __send_ipi_mask(const struct cpumask *mask, int vector) } else if (apic_id < min && max - apic_id < KVM_IPI_CLUSTER_SIZE) { ipi_bitmap <<= min - apic_id; min = apic_id; - } else if (apic_id < min + KVM_IPI_CLUSTER_SIZE) { + } else if (apic_id > min && apic_id < min + KVM_IPI_CLUSTER_SIZE) { max = apic_id < max ? max : apic_id; } else { ret = kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap, @@ -547,29 +571,58 @@ static void __init kvm_smp_prepare_boot_cpu(void) kvm_spinlock_init(); } -static void kvm_guest_cpu_offline(void) +static int kvm_cpu_down_prepare(unsigned int cpu) { - kvm_disable_steal_time(); - if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) - wrmsrl(MSR_KVM_PV_EOI_EN, 0); - kvm_pv_disable_apf(); - apf_task_wake_all(); + unsigned long flags; + + local_irq_save(flags); + kvm_guest_cpu_offline(false); + local_irq_restore(flags); + return 0; } -static int kvm_cpu_online(unsigned int cpu) +#endif + +static int kvm_suspend(void) { - local_irq_disable(); - kvm_guest_cpu_init(); - local_irq_enable(); + u64 val = 0; + + kvm_guest_cpu_offline(false); + +#ifdef CONFIG_ARCH_CPUIDLE_HALTPOLL + if (kvm_para_has_feature(KVM_FEATURE_POLL_CONTROL)) + rdmsrl(MSR_KVM_POLL_CONTROL, val); + has_guest_poll = !(val & 1); +#endif return 0; } -static int kvm_cpu_down_prepare(unsigned int cpu) +static void kvm_resume(void) { - local_irq_disable(); - kvm_guest_cpu_offline(); - local_irq_enable(); - return 0; + kvm_cpu_online(raw_smp_processor_id()); + +#ifdef CONFIG_ARCH_CPUIDLE_HALTPOLL + if (kvm_para_has_feature(KVM_FEATURE_POLL_CONTROL) && has_guest_poll) + wrmsrl(MSR_KVM_POLL_CONTROL, 0); +#endif +} + +static struct syscore_ops kvm_syscore_ops = { + .suspend = kvm_suspend, + .resume = kvm_resume, +}; + +/* + * After a PV feature is registered, the host will keep writing to the + * registered memory location. If the guest happens to shutdown, this memory + * won't be valid. In cases like kexec, in which you install a new kernel, this + * means a random memory location will be kept being written. + */ +#ifdef CONFIG_KEXEC_CORE +static void kvm_crash_shutdown(struct pt_regs *regs) +{ + kvm_guest_cpu_offline(true); + native_machine_crash_shutdown(regs); } #endif @@ -649,6 +702,12 @@ static void __init kvm_guest_init(void) kvm_guest_cpu_init(); #endif +#ifdef CONFIG_KEXEC_CORE + machine_ops.crash_shutdown = kvm_crash_shutdown; +#endif + + register_syscore_ops(&kvm_syscore_ops); + /* * Hard lockup detection is enabled by default. Disable it, as guests * can get false positives too easily, for example if the host is |