From: Marian Rotariu <marian.c.rotariu@xxxxxxxxx> The introspection tool uses this function to check the hardware support for EPT switching, which can be used either to singlestep vCPUs on a unprotected EPT view or to use #VE in order to avoid filter out VM-exits caused by EPT violations. Signed-off-by: Marian Rotariu <marian.c.rotariu@xxxxxxxxx> Co-developed-by: Ștefan Șicleru <ssicleru@xxxxxxxxxxxxxxx> Signed-off-by: Ștefan Șicleru <ssicleru@xxxxxxxxxxxxxxx> Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx> --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu/mmu.c | 12 ++-- arch/x86/kvm/vmx/vmx.c | 98 +++++++++++++++++++++++++++++++++ arch/x86/kvm/vmx/vmx.h | 1 + 4 files changed, 108 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index bd45778e0904..1035308940fe 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -421,6 +421,7 @@ struct kvm_mmu { void (*update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *spte, const void *pte); hpa_t root_hpa; + hpa_t root_hpa_altviews[KVM_MAX_EPT_VIEWS]; gpa_t root_pgd; union kvm_mmu_role mmu_role; u8 root_level; diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 0b6527a1ebe6..553425ab3518 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -3760,8 +3760,11 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, if (free_active_root) { if (mmu->shadow_root_level >= PT64_ROOT_4LEVEL && (mmu->root_level >= PT64_ROOT_4LEVEL || mmu->direct_map)) { - mmu_free_root_page(vcpu->kvm, &mmu->root_hpa, - &invalid_list); + for (i = 0; i < KVM_MAX_EPT_VIEWS; i++) + mmu_free_root_page(vcpu->kvm, + mmu->root_hpa_altviews + i, + &invalid_list); + mmu->root_hpa = INVALID_PAGE; } else { for (i = 0; i < 4; ++i) if (mmu->pae_root[i] != 0) @@ -3821,9 +3824,10 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) shadow_root_level, true, i); if (!VALID_PAGE(root)) return -ENOSPC; - if (i == 0) - vcpu->arch.mmu->root_hpa = root; + vcpu->arch.mmu->root_hpa_altviews[i] = root; } + vcpu->arch.mmu->root_hpa = + vcpu->arch.mmu->root_hpa_altviews[kvm_get_ept_view(vcpu)]; } else if (shadow_root_level == PT32E_ROOT_LEVEL) { for (i = 0; i < 4; ++i) { MMU_WARN_ON(VALID_PAGE(vcpu->arch.mmu->pae_root[i])); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0256c3a93c87..2024ef4d9a74 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -3124,6 +3124,32 @@ u64 construct_eptp(struct kvm_vcpu *vcpu, unsigned long root_hpa) return eptp; } +static void vmx_construct_eptp_with_index(struct kvm_vcpu *vcpu, + unsigned short view) +{ + struct vcpu_vmx *vmx = to_vmx(vcpu); + u64 *eptp_list = NULL; + + if (!vmx->eptp_list_pg) + return; + + eptp_list = phys_to_virt(page_to_phys(vmx->eptp_list_pg)); + + if (!eptp_list) + return; + + eptp_list[view] = construct_eptp(vcpu, + vcpu->arch.mmu->root_hpa_altviews[view]); +} + +static void vmx_construct_eptp_list(struct kvm_vcpu *vcpu) +{ + unsigned short view; + + for (view = 0; view < KVM_MAX_EPT_VIEWS; view++) + vmx_construct_eptp_with_index(vcpu, view); +} + void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, unsigned long pgd) { struct kvm *kvm = vcpu->kvm; @@ -3135,6 +3161,8 @@ void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, unsigned long pgd) eptp = construct_eptp(vcpu, pgd); vmcs_write64(EPT_POINTER, eptp); + vmx_construct_eptp_list(vcpu); + if (kvm_x86_ops.tlb_remote_flush) { spin_lock(&to_kvm_vmx(kvm)->ept_pointer_lock); to_vmx(vcpu)->ept_pointer = eptp; @@ -4336,6 +4364,15 @@ static void ept_set_mmio_spte_mask(void) kvm_mmu_set_mmio_spte_mask(VMX_EPT_MISCONFIG_WX_VALUE, 0); } +static int vmx_alloc_eptp_list_page(struct vcpu_vmx *vmx) +{ + vmx->eptp_list_pg = alloc_page(GFP_KERNEL | __GFP_ZERO); + if (!vmx->eptp_list_pg) + return -ENOMEM; + + return 0; +} + #define VMX_XSS_EXIT_BITMAP 0 /* @@ -4426,6 +4463,10 @@ static void init_vmcs(struct vcpu_vmx *vmx) if (cpu_has_vmx_encls_vmexit()) vmcs_write64(ENCLS_EXITING_BITMAP, -1ull); + if (vmx->eptp_list_pg) + vmcs_write64(EPTP_LIST_ADDRESS, + page_to_phys(vmx->eptp_list_pg)); + if (vmx_pt_mode_is_host_guest()) { memset(&vmx->pt_desc, 0, sizeof(vmx->pt_desc)); /* Bit[6~0] are forced to 1, writes are ignored. */ @@ -5913,6 +5954,24 @@ static void vmx_dump_dtsel(char *name, uint32_t limit) vmcs_readl(limit + GUEST_GDTR_BASE - GUEST_GDTR_LIMIT)); } +static void dump_eptp_list(void) +{ + phys_addr_t eptp_list_phys, *eptp_list = NULL; + int i; + + eptp_list_phys = (phys_addr_t)vmcs_read64(EPTP_LIST_ADDRESS); + if (!eptp_list_phys) + return; + + eptp_list = phys_to_virt(eptp_list_phys); + + pr_err("*** EPTP Switching ***\n"); + pr_err("EPTP List Address: %p (phys %p)\n", + eptp_list, (void *)eptp_list_phys); + for (i = 0; i < KVM_MAX_EPT_VIEWS; i++) + pr_err("%d: %016llx\n", i, *(eptp_list + i)); +} + void dump_vmcs(void) { u32 vmentry_ctl, vmexit_ctl; @@ -6061,6 +6120,23 @@ void dump_vmcs(void) if (secondary_exec_control & SECONDARY_EXEC_ENABLE_VPID) pr_err("Virtual processor ID = 0x%04x\n", vmcs_read16(VIRTUAL_PROCESSOR_ID)); + + dump_eptp_list(); +} + +static unsigned int update_ept_view(struct vcpu_vmx *vmx) +{ + u64 *eptp_list = phys_to_virt(page_to_phys(vmx->eptp_list_pg)); + u64 eptp = vmcs_read64(EPT_POINTER); + unsigned int view; + + for (view = 0; view < KVM_MAX_EPT_VIEWS; view++) + if (eptp_list[view] == eptp) { + vmx->view = view; + break; + } + + return vmx->view; } /* @@ -6073,6 +6149,13 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) u32 exit_reason = vmx->exit_reason; u32 vectoring_info = vmx->idt_vectoring_info; + if (vmx->eptp_list_pg) { + unsigned int view = update_ept_view(vmx); + struct kvm_mmu *mmu = vcpu->arch.mmu; + + mmu->root_hpa = mmu->root_hpa_altviews[view]; + } + /* * Flush logged GPAs PML buffer, this will make dirty_bitmap more * updated. Another good is, in kvm_vm_ioctl_get_dirty_log, before @@ -6951,12 +7034,21 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) return exit_fastpath; } +static void vmx_destroy_eptp_list_page(struct vcpu_vmx *vmx) +{ + if (vmx->eptp_list_pg) { + __free_page(vmx->eptp_list_pg); + vmx->eptp_list_pg = NULL; + } +} + static void vmx_free_vcpu(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); if (enable_pml) vmx_destroy_pml_buffer(vmx); + vmx_destroy_eptp_list_page(vmx); free_vpid(vmx->vpid); nested_vmx_free_vcpu(vcpu); free_loaded_vmcs(vmx->loaded_vmcs); @@ -7021,6 +7113,12 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) if (err < 0) goto free_pml; + if (kvm_eptp_switching_supported) { + err = vmx_alloc_eptp_list_page(vmx); + if (err) + goto free_pml; + } + msr_bitmap = vmx->vmcs01.msr_bitmap; vmx_disable_intercept_for_msr(NULL, msr_bitmap, MSR_IA32_TSC, MSR_TYPE_R); vmx_disable_intercept_for_msr(NULL, msr_bitmap, MSR_FS_BASE, MSR_TYPE_RW); diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index 14f0b9102d58..4e2f86458ca2 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -297,6 +297,7 @@ struct vcpu_vmx { struct pt_desc pt_desc; + struct page *eptp_list_pg; /* The view this vcpu operates on. */ u16 view; }; _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization