diff options
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/mmu_internal.h | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/spte.c | 21 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/spte.h | 10 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/run_flags.h | 10 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 8 |
6 files changed, 48 insertions, 5 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index b4a391929cdb..6a172c7630f3 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1451,6 +1451,7 @@ struct kvm_arch { bool x2apic_format; bool x2apic_broadcast_quirk_disabled; + bool has_mapped_host_mmio; bool guest_can_read_msr_platform_info; bool exception_payload_enabled; diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h index db8f33e4de62..65f3c89d7c5d 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -103,6 +103,9 @@ struct kvm_mmu_page { int root_count; refcount_t tdp_mmu_root_count; }; + + bool has_mapped_host_mmio; + union { /* These two members aren't used for TDP MMU */ struct { diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c index 3f16c91aa042..df31039b5d63 100644 --- a/arch/x86/kvm/mmu/spte.c +++ b/arch/x86/kvm/mmu/spte.c @@ -138,6 +138,22 @@ static bool kvm_is_mmio_pfn(kvm_pfn_t pfn, int *is_host_mmio) return *is_host_mmio; } +static void kvm_track_host_mmio_mapping(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *root = root_to_sp(vcpu->arch.mmu->root.hpa); + + if (root) + WRITE_ONCE(root->has_mapped_host_mmio, true); + else + WRITE_ONCE(vcpu->kvm->arch.has_mapped_host_mmio, true); + + /* + * Force vCPUs to exit and flush CPU buffers if the vCPU is using the + * affected root(s). + */ + kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_OUTSIDE_GUEST_MODE); +} + /* * Returns true if the SPTE needs to be updated atomically due to having bits * that may be changed without holding mmu_lock, and for which KVM must not @@ -276,6 +292,11 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, mark_page_dirty_in_slot(vcpu->kvm, slot, gfn); } + if (static_branch_unlikely(&cpu_buf_vm_clear) && + !kvm_vcpu_can_access_host_mmio(vcpu) && + kvm_is_mmio_pfn(pfn, &is_host_mmio)) + kvm_track_host_mmio_mapping(vcpu); + *new_spte = spte; return wrprot; } diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h index 1e94f081bdaf..3133f066927e 100644 --- a/arch/x86/kvm/mmu/spte.h +++ b/arch/x86/kvm/mmu/spte.h @@ -280,6 +280,16 @@ static inline bool is_mirror_sptep(tdp_ptep_t sptep) return is_mirror_sp(sptep_to_sp(rcu_dereference(sptep))); } +static inline bool kvm_vcpu_can_access_host_mmio(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *root = root_to_sp(vcpu->arch.mmu->root.hpa); + + if (root) + return READ_ONCE(root->has_mapped_host_mmio); + + return READ_ONCE(vcpu->kvm->arch.has_mapped_host_mmio); +} + static inline bool is_mmio_spte(struct kvm *kvm, u64 spte) { return (spte & shadow_mmio_mask) == kvm->arch.shadow_mmio_value && diff --git a/arch/x86/kvm/vmx/run_flags.h b/arch/x86/kvm/vmx/run_flags.h index 6a9bfdfbb6e5..2f20fb170def 100644 --- a/arch/x86/kvm/vmx/run_flags.h +++ b/arch/x86/kvm/vmx/run_flags.h @@ -2,10 +2,12 @@ #ifndef __KVM_X86_VMX_RUN_FLAGS_H #define __KVM_X86_VMX_RUN_FLAGS_H -#define VMX_RUN_VMRESUME_SHIFT 0 -#define VMX_RUN_SAVE_SPEC_CTRL_SHIFT 1 +#define VMX_RUN_VMRESUME_SHIFT 0 +#define VMX_RUN_SAVE_SPEC_CTRL_SHIFT 1 +#define VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO_SHIFT 2 -#define VMX_RUN_VMRESUME BIT(VMX_RUN_VMRESUME_SHIFT) -#define VMX_RUN_SAVE_SPEC_CTRL BIT(VMX_RUN_SAVE_SPEC_CTRL_SHIFT) +#define VMX_RUN_VMRESUME BIT(VMX_RUN_VMRESUME_SHIFT) +#define VMX_RUN_SAVE_SPEC_CTRL BIT(VMX_RUN_SAVE_SPEC_CTRL_SHIFT) +#define VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO BIT(VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO_SHIFT) #endif /* __KVM_X86_VMX_RUN_FLAGS_H */ diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 4953846cb30d..3025b11007fd 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -75,6 +75,8 @@ #include "vmx_onhyperv.h" #include "posted_intr.h" +#include "mmu/spte.h" + MODULE_AUTHOR("Qumranet"); MODULE_DESCRIPTION("KVM support for VMX (Intel VT-x) extensions"); MODULE_LICENSE("GPL"); @@ -963,6 +965,10 @@ unsigned int __vmx_vcpu_run_flags(struct vcpu_vmx *vmx) if (!msr_write_intercepted(vmx, MSR_IA32_SPEC_CTRL)) flags |= VMX_RUN_SAVE_SPEC_CTRL; + if (static_branch_unlikely(&cpu_buf_vm_clear) && + kvm_vcpu_can_access_host_mmio(&vmx->vcpu)) + flags |= VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO; + return flags; } @@ -7290,7 +7296,7 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu, if (static_branch_unlikely(&vmx_l1d_should_flush)) vmx_l1d_flush(vcpu); else if (static_branch_unlikely(&cpu_buf_vm_clear) && - kvm_arch_has_assigned_device(vcpu->kvm)) + (flags & VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO)) mds_clear_cpu_buffers(); vmx_disable_fb_clear(vmx); |