From eb4b248e152d3ecf189b9d32c04961360dbd938a Mon Sep 17 00:00:00 2001 From: Junaid Shahid Date: Wed, 27 Jun 2018 14:59:14 -0700 Subject: [PATCH] kvm: vmx: Support INVPCID in shadow paging mode Implement support for INVPCID in shadow paging mode as well. Signed-off-by: Junaid Shahid Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu.c | 18 +++++++ arch/x86/kvm/vmx.c | 96 +++++++++++++++++++++++++++++++-- 3 files changed, 112 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index c2b4df8a03cd..1c253f15f9cd 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1317,6 +1317,7 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu); int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t gva, u64 error_code, void *insn, int insn_len); void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva); +void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid); void kvm_mmu_new_cr3(struct kvm_vcpu *vcpu, gpa_t new_cr3); void kvm_enable_tdp(void); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index d3a04cf6514b..2af15db12ccd 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -5187,6 +5187,24 @@ void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva) } EXPORT_SYMBOL_GPL(kvm_mmu_invlpg); +void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid) +{ + struct kvm_mmu *mmu = &vcpu->arch.mmu; + + if (pcid == kvm_get_active_pcid(vcpu)) { + mmu->invlpg(vcpu, gva); + kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); + } + + ++vcpu->stat.invlpg; + + /* + * Mappings not reachable via the current cr3 will be synced when + * switching to that cr3, so nothing needs to be done here for them. + */ +} +EXPORT_SYMBOL_GPL(kvm_mmu_invpcid_gva); + void kvm_enable_tdp(void) { tdp_enabled = true; diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 903c130bb811..80be024cb979 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3065,7 +3065,7 @@ static bool vmx_rdtscp_supported(void) static bool vmx_invpcid_supported(void) { - return cpu_has_vmx_invpcid() && enable_ept; + return cpu_has_vmx_invpcid(); } /* @@ -6101,8 +6101,6 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx) if (!enable_ept) { exec_control &= ~SECONDARY_EXEC_ENABLE_EPT; enable_unrestricted_guest = 0; - /* Enable INVPCID for non-ept guests may cause performance regression. */ - exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID; } if (!enable_unrestricted_guest) exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST; @@ -8756,6 +8754,97 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) return kvm_skip_emulated_instruction(vcpu); } +static int handle_invpcid(struct kvm_vcpu *vcpu) +{ + u32 vmx_instruction_info; + unsigned long type; + bool pcid_enabled; + gva_t gva; + struct x86_exception e; + struct { + u64 pcid; + u64 gla; + } operand; + + if (!guest_cpuid_has(vcpu, X86_FEATURE_INVPCID)) { + kvm_queue_exception(vcpu, UD_VECTOR); + return 1; + } + + vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO); + type = kvm_register_readl(vcpu, (vmx_instruction_info >> 28) & 0xf); + + if (type > 3) { + kvm_inject_gp(vcpu, 0); + return 1; + } + + /* According to the Intel instruction reference, the memory operand + * is read even if it isn't needed (e.g., for type==all) + */ + if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION), + vmx_instruction_info, false, &gva)) + return 1; + + if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) { + kvm_inject_page_fault(vcpu, &e); + return 1; + } + + if (operand.pcid >> 12 != 0) { + kvm_inject_gp(vcpu, 0); + return 1; + } + + pcid_enabled = kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE); + + switch (type) { + case INVPCID_TYPE_INDIV_ADDR: + if ((!pcid_enabled && (operand.pcid != 0)) || + is_noncanonical_address(operand.gla, vcpu)) { + kvm_inject_gp(vcpu, 0); + return 1; + } + kvm_mmu_invpcid_gva(vcpu, operand.gla, operand.pcid); + return kvm_skip_emulated_instruction(vcpu); + + case INVPCID_TYPE_SINGLE_CTXT: + if (!pcid_enabled && (operand.pcid != 0)) { + kvm_inject_gp(vcpu, 0); + return 1; + } + + if (kvm_get_active_pcid(vcpu) == operand.pcid) { + kvm_mmu_sync_roots(vcpu); + kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); + } + + /* + * If the current cr3 does not use the given PCID, then nothing + * needs to be done here because a resync will happen anyway + * before switching to any other CR3. + */ + + return kvm_skip_emulated_instruction(vcpu); + + case INVPCID_TYPE_ALL_NON_GLOBAL: + /* + * Currently, KVM doesn't mark global entries in the shadow + * page tables, so a non-global flush just degenerates to a + * global flush. If needed, we could optimize this later by + * keeping track of global entries in shadow page tables. + */ + + /* fall-through */ + case INVPCID_TYPE_ALL_INCL_GLOBAL: + kvm_mmu_unload(vcpu); + return kvm_skip_emulated_instruction(vcpu); + + default: + BUG(); /* We have already checked above that type <= 3 */ + } +} + static int handle_pml_full(struct kvm_vcpu *vcpu) { unsigned long exit_qualification; @@ -8959,6 +9048,7 @@ static int (*const kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = { [EXIT_REASON_XSAVES] = handle_xsaves, [EXIT_REASON_XRSTORS] = handle_xrstors, [EXIT_REASON_PML_FULL] = handle_pml_full, + [EXIT_REASON_INVPCID] = handle_invpcid, [EXIT_REASON_VMFUNC] = handle_vmfunc, [EXIT_REASON_PREEMPTION_TIMER] = handle_preemption_timer, };