diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index c92349e2f621..0dc9505ae9a2 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -1105,14 +1105,6 @@ static int vmx_restore_vmx_misc(struct vcpu_vmx *vmx, u64 data) vmx->nested.msrs.misc_low = data; vmx->nested.msrs.misc_high = data >> 32; - /* - * If L1 has read-only VM-exit information fields, use the - * less permissive vmx_vmwrite_bitmap to specify write - * permissions for the shadow VMCS. - */ - if (enable_shadow_vmcs && !nested_cpu_has_vmwrite_any_field(&vmx->vcpu)) - vmcs_write64(VMWRITE_BITMAP, __pa(vmx_vmwrite_bitmap)); - return 0; } @@ -1301,41 +1293,27 @@ int vmx_get_vmx_msr(struct nested_vmx_msrs *msrs, u32 msr_index, u64 *pdata) } /* - * Copy the writable VMCS shadow fields back to the VMCS12, in case - * they have been modified by the L1 guest. Note that the "read-only" - * VM-exit information fields are actually writable if the vCPU is - * configured to support "VMWRITE to any supported field in the VMCS." + * Copy the writable VMCS shadow fields back to the VMCS12, in case they have + * been modified by the L1 guest. Note, "writable" in this context means + * "writable by the guest", i.e. tagged SHADOW_FIELD_RW; the set of + * fields tagged SHADOW_FIELD_RO may or may not align with the "read-only" + * VM-exit information fields (which are actually writable if the vCPU is + * configured to support "VMWRITE to any supported field in the VMCS"). */ static void copy_shadow_to_vmcs12(struct vcpu_vmx *vmx) { - const u16 *fields[] = { - shadow_read_write_fields, - shadow_read_only_fields - }; - const int max_fields[] = { - max_shadow_read_write_fields, - max_shadow_read_only_fields - }; - int i, q; - unsigned long field; - u64 field_value; struct vmcs *shadow_vmcs = vmx->vmcs01.shadow_vmcs; + struct vmcs12 *vmcs12 = get_vmcs12(&vmx->vcpu); + unsigned long field; + int i; preempt_disable(); vmcs_load(shadow_vmcs); - for (q = 0; q < ARRAY_SIZE(fields); q++) { - for (i = 0; i < max_fields[q]; i++) { - field = fields[q][i]; - field_value = __vmcs_readl(field); - vmcs12_write_any(get_vmcs12(&vmx->vcpu), field, field_value); - } - /* - * Skip the VM-exit information fields if they are read-only. - */ - if (!nested_cpu_has_vmwrite_any_field(&vmx->vcpu)) - break; + for (i = 0; i < max_shadow_read_write_fields; i++) { + field = shadow_read_write_fields[i]; + vmcs12_write_any(vmcs12, field, __vmcs_readl(field)); } vmcs_clear(shadow_vmcs); @@ -4517,6 +4495,24 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) * path of prepare_vmcs02. */ break; + +#define SHADOW_FIELD_RO(x) case x: +#include "vmcs_shadow_fields.h" + /* + * L1 can read these fields without exiting, ensure the + * shadow VMCS is up-to-date. + */ + if (enable_shadow_vmcs) { + preempt_disable(); + vmcs_load(vmx->vmcs01.shadow_vmcs); + + __vmcs_writel(field, field_value); + + vmcs_clear(vmx->vmcs01.shadow_vmcs); + vmcs_load(vmx->loaded_vmcs->vmcs); + preempt_enable(); + } + /* fall through */ default: vmx->nested.dirty_vmcs12 = true; break; @@ -5470,14 +5466,8 @@ error_guest_mode: void nested_vmx_vcpu_setup(void) { if (enable_shadow_vmcs) { - /* - * At vCPU creation, "VMWRITE to any supported field - * in the VMCS" is supported, so use the more - * permissive vmx_vmread_bitmap to specify both read - * and write permissions for the shadow VMCS. - */ vmcs_write64(VMREAD_BITMAP, __pa(vmx_vmread_bitmap)); - vmcs_write64(VMWRITE_BITMAP, __pa(vmx_vmread_bitmap)); + vmcs_write64(VMWRITE_BITMAP, __pa(vmx_vmwrite_bitmap)); } }