diff options
| -rw-r--r-- | arch/x86/kvm/vmx.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 94833e2fe78c..1a30fd5c3fb2 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -42,6 +42,7 @@ #include <asm/i387.h> #include <asm/xcr.h> #include <asm/perf_event.h> +#include <asm/kexec.h> #include "trace.h" @@ -987,6 +988,46 @@ static void vmcs_load(struct vmcs *vmcs) vmcs, phys_addr); } +#ifdef CONFIG_KEXEC +/* + * This bitmap is used to indicate whether the vmclear + * operation is enabled on all cpus. All disabled by + * default. + */ +static cpumask_t crash_vmclear_enabled_bitmap = CPU_MASK_NONE; + +static inline void crash_enable_local_vmclear(int cpu) +{ + cpumask_set_cpu(cpu, &crash_vmclear_enabled_bitmap); +} + +static inline void crash_disable_local_vmclear(int cpu) +{ + cpumask_clear_cpu(cpu, &crash_vmclear_enabled_bitmap); +} + +static inline int crash_local_vmclear_enabled(int cpu) +{ + return cpumask_test_cpu(cpu, &crash_vmclear_enabled_bitmap); +} + +static void crash_vmclear_local_loaded_vmcss(void) +{ + int cpu = raw_smp_processor_id(); + struct loaded_vmcs *v; + + if (!crash_local_vmclear_enabled(cpu)) + return; + + list_for_each_entry(v, &per_cpu(loaded_vmcss_on_cpu, cpu), + loaded_vmcss_on_cpu_link) + vmcs_clear(v->vmcs); +} +#else +static inline void crash_enable_local_vmclear(int cpu) { } +static inline void crash_disable_local_vmclear(int cpu) { } +#endif /* CONFIG_KEXEC */ + static void __loaded_vmcs_clear(void *arg) { struct loaded_vmcs *loaded_vmcs = arg; @@ -996,6 +1037,7 @@ static void __loaded_vmcs_clear(void *arg) return; /* vcpu migration can race with cpu offline */ if (per_cpu(current_vmcs, cpu) == loaded_vmcs->vmcs) per_cpu(current_vmcs, cpu) = NULL; + crash_disable_local_vmclear(cpu); list_del(&loaded_vmcs->loaded_vmcss_on_cpu_link); /* @@ -1007,6 +1049,7 @@ static void __loaded_vmcs_clear(void *arg) smp_wmb(); loaded_vmcs_init(loaded_vmcs); + crash_enable_local_vmclear(cpu); } static void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs) @@ -1530,6 +1573,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu) kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); local_irq_disable(); + crash_disable_local_vmclear(cpu); /* * Read loaded_vmcs->cpu should be before fetching @@ -1540,6 +1584,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu) list_add(&vmx->loaded_vmcs->loaded_vmcss_on_cpu_link, &per_cpu(loaded_vmcss_on_cpu, cpu)); + crash_enable_local_vmclear(cpu); local_irq_enable(); /* @@ -2353,6 +2398,18 @@ static int hardware_enable(void *garbage) return -EBUSY; INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu)); + + /* + * Now we can enable the vmclear operation in kdump + * since the loaded_vmcss_on_cpu list on this cpu + * has been initialized. + * + * Though the cpu is not in VMX operation now, there + * is no problem to enable the vmclear operation + * for the loaded_vmcss_on_cpu list is empty! + */ + crash_enable_local_vmclear(cpu); + rdmsrl(MSR_IA32_FEATURE_CONTROL, old); test_bits = FEATURE_CONTROL_LOCKED; @@ -7383,6 +7440,11 @@ static int __init vmx_init(void) if (r) goto out3; +#ifdef CONFIG_KEXEC + rcu_assign_pointer(crash_vmclear_loaded_vmcss, + crash_vmclear_local_loaded_vmcss); +#endif + vmx_disable_intercept_for_msr(MSR_FS_BASE, false); vmx_disable_intercept_for_msr(MSR_GS_BASE, false); vmx_disable_intercept_for_msr(MSR_KERNEL_GS_BASE, true); @@ -7420,6 +7482,11 @@ static void __exit vmx_exit(void) free_page((unsigned long)vmx_io_bitmap_b); free_page((unsigned long)vmx_io_bitmap_a); +#ifdef CONFIG_KEXEC + rcu_assign_pointer(crash_vmclear_loaded_vmcss, NULL); + synchronize_rcu(); +#endif + kvm_exit(); } |