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Diffstat (limited to 'arch/x86/kvm/vmx.c')
-rw-r--r--arch/x86/kvm/vmx.c98
1 files changed, 65 insertions, 33 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 4555077d69ce..02edd9960e9d 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -174,6 +174,7 @@ module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO);
* refer SDM volume 3b section 21.6.13 & 22.1.3.
*/
static unsigned int ple_gap = KVM_DEFAULT_PLE_GAP;
+module_param(ple_gap, uint, 0444);
static unsigned int ple_window = KVM_VMX_DEFAULT_PLE_WINDOW;
module_param(ple_window, uint, 0444);
@@ -984,6 +985,7 @@ struct vcpu_vmx {
struct shared_msr_entry *guest_msrs;
int nmsrs;
int save_nmsrs;
+ bool guest_msrs_dirty;
unsigned long host_idt_base;
#ifdef CONFIG_X86_64
u64 msr_host_kernel_gs_base;
@@ -1306,7 +1308,7 @@ static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked);
static bool nested_vmx_is_page_fault_vmexit(struct vmcs12 *vmcs12,
u16 error_code);
static void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu);
-static void __always_inline vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
+static __always_inline void vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type);
static DEFINE_PER_CPU(struct vmcs *, vmxarea);
@@ -1610,12 +1612,6 @@ static int nested_enable_evmcs(struct kvm_vcpu *vcpu,
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- /* We don't support disabling the feature for simplicity. */
- if (vmx->nested.enlightened_vmcs_enabled)
- return 0;
-
- vmx->nested.enlightened_vmcs_enabled = true;
-
/*
* vmcs_version represents the range of supported Enlightened VMCS
* versions: lower 8 bits is the minimal version, higher 8 bits is the
@@ -1625,6 +1621,12 @@ static int nested_enable_evmcs(struct kvm_vcpu *vcpu,
if (vmcs_version)
*vmcs_version = (KVM_EVMCS_VERSION << 8) | 1;
+ /* We don't support disabling the feature for simplicity. */
+ if (vmx->nested.enlightened_vmcs_enabled)
+ return 0;
+
+ vmx->nested.enlightened_vmcs_enabled = true;
+
vmx->nested.msrs.pinbased_ctls_high &= ~EVMCS1_UNSUPPORTED_PINCTRL;
vmx->nested.msrs.entry_ctls_high &= ~EVMCS1_UNSUPPORTED_VMENTRY_CTRL;
vmx->nested.msrs.exit_ctls_high &= ~EVMCS1_UNSUPPORTED_VMEXIT_CTRL;
@@ -2897,6 +2899,20 @@ static void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
vmx->req_immediate_exit = false;
+ /*
+ * Note that guest MSRs to be saved/restored can also be changed
+ * when guest state is loaded. This happens when guest transitions
+ * to/from long-mode by setting MSR_EFER.LMA.
+ */
+ if (!vmx->loaded_cpu_state || vmx->guest_msrs_dirty) {
+ vmx->guest_msrs_dirty = false;
+ for (i = 0; i < vmx->save_nmsrs; ++i)
+ kvm_set_shared_msr(vmx->guest_msrs[i].index,
+ vmx->guest_msrs[i].data,
+ vmx->guest_msrs[i].mask);
+
+ }
+
if (vmx->loaded_cpu_state)
return;
@@ -2957,11 +2973,6 @@ static void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
vmcs_writel(HOST_GS_BASE, gs_base);
host_state->gs_base = gs_base;
}
-
- for (i = 0; i < vmx->save_nmsrs; ++i)
- kvm_set_shared_msr(vmx->guest_msrs[i].index,
- vmx->guest_msrs[i].data,
- vmx->guest_msrs[i].mask);
}
static void vmx_prepare_switch_to_host(struct vcpu_vmx *vmx)
@@ -3436,6 +3447,7 @@ static void setup_msrs(struct vcpu_vmx *vmx)
move_msr_up(vmx, index, save_nmsrs++);
vmx->save_nmsrs = save_nmsrs;
+ vmx->guest_msrs_dirty = true;
if (cpu_has_vmx_msr_bitmap())
vmx_update_msr_bitmap(&vmx->vcpu);
@@ -3452,11 +3464,9 @@ static u64 vmx_read_l1_tsc_offset(struct kvm_vcpu *vcpu)
return vcpu->arch.tsc_offset;
}
-/*
- * writes 'offset' into guest's timestamp counter offset register
- */
-static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
+static u64 vmx_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
{
+ u64 active_offset = offset;
if (is_guest_mode(vcpu)) {
/*
* We're here if L1 chose not to trap WRMSR to TSC. According
@@ -3464,17 +3474,16 @@ static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
* set for L2 remains unchanged, and still needs to be added
* to the newly set TSC to get L2's TSC.
*/
- struct vmcs12 *vmcs12;
- /* recalculate vmcs02.TSC_OFFSET: */
- vmcs12 = get_vmcs12(vcpu);
- vmcs_write64(TSC_OFFSET, offset +
- (nested_cpu_has(vmcs12, CPU_BASED_USE_TSC_OFFSETING) ?
- vmcs12->tsc_offset : 0));
+ struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+ if (nested_cpu_has(vmcs12, CPU_BASED_USE_TSC_OFFSETING))
+ active_offset += vmcs12->tsc_offset;
} else {
trace_kvm_write_tsc_offset(vcpu->vcpu_id,
vmcs_read64(TSC_OFFSET), offset);
- vmcs_write64(TSC_OFFSET, offset);
}
+
+ vmcs_write64(TSC_OFFSET, active_offset);
+ return active_offset;
}
/*
@@ -5944,7 +5953,7 @@ static void free_vpid(int vpid)
spin_unlock(&vmx_vpid_lock);
}
-static void __always_inline vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
+static __always_inline void vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type)
{
int f = sizeof(unsigned long);
@@ -5982,7 +5991,7 @@ static void __always_inline vmx_disable_intercept_for_msr(unsigned long *msr_bit
}
}
-static void __always_inline vmx_enable_intercept_for_msr(unsigned long *msr_bitmap,
+static __always_inline void vmx_enable_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type)
{
int f = sizeof(unsigned long);
@@ -6020,7 +6029,7 @@ static void __always_inline vmx_enable_intercept_for_msr(unsigned long *msr_bitm
}
}
-static void __always_inline vmx_set_intercept_for_msr(unsigned long *msr_bitmap,
+static __always_inline void vmx_set_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type, bool value)
{
if (value)
@@ -8664,8 +8673,6 @@ static int copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx)
struct vmcs12 *vmcs12 = vmx->nested.cached_vmcs12;
struct hv_enlightened_vmcs *evmcs = vmx->nested.hv_evmcs;
- vmcs12->hdr.revision_id = evmcs->revision_id;
-
/* HV_VMX_ENLIGHTENED_CLEAN_FIELD_NONE */
vmcs12->tpr_threshold = evmcs->tpr_threshold;
vmcs12->guest_rip = evmcs->guest_rip;
@@ -9369,7 +9376,30 @@ static int nested_vmx_handle_enlightened_vmptrld(struct kvm_vcpu *vcpu,
vmx->nested.hv_evmcs = kmap(vmx->nested.hv_evmcs_page);
- if (vmx->nested.hv_evmcs->revision_id != VMCS12_REVISION) {
+ /*
+ * Currently, KVM only supports eVMCS version 1
+ * (== KVM_EVMCS_VERSION) and thus we expect guest to set this
+ * value to first u32 field of eVMCS which should specify eVMCS
+ * VersionNumber.
+ *
+ * Guest should be aware of supported eVMCS versions by host by
+ * examining CPUID.0x4000000A.EAX[0:15]. Host userspace VMM is
+ * expected to set this CPUID leaf according to the value
+ * returned in vmcs_version from nested_enable_evmcs().
+ *
+ * However, it turns out that Microsoft Hyper-V fails to comply
+ * to their own invented interface: When Hyper-V use eVMCS, it
+ * just sets first u32 field of eVMCS to revision_id specified
+ * in MSR_IA32_VMX_BASIC. Instead of used eVMCS version number
+ * which is one of the supported versions specified in
+ * CPUID.0x4000000A.EAX[0:15].
+ *
+ * To overcome Hyper-V bug, we accept here either a supported
+ * eVMCS version or VMCS12 revision_id as valid values for first
+ * u32 field of eVMCS.
+ */
+ if ((vmx->nested.hv_evmcs->revision_id != KVM_EVMCS_VERSION) &&
+ (vmx->nested.hv_evmcs->revision_id != VMCS12_REVISION)) {
nested_release_evmcs(vcpu);
return 0;
}
@@ -9390,9 +9420,11 @@ static int nested_vmx_handle_enlightened_vmptrld(struct kvm_vcpu *vcpu,
* present in struct hv_enlightened_vmcs, ...). Make sure there
* are no leftovers.
*/
- if (from_launch)
- memset(vmx->nested.cached_vmcs12, 0,
- sizeof(*vmx->nested.cached_vmcs12));
+ if (from_launch) {
+ struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+ memset(vmcs12, 0, sizeof(*vmcs12));
+ vmcs12->hdr.revision_id = VMCS12_REVISION;
+ }
}
return 1;
@@ -15062,7 +15094,7 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
.has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
.read_l1_tsc_offset = vmx_read_l1_tsc_offset,
- .write_tsc_offset = vmx_write_tsc_offset,
+ .write_l1_tsc_offset = vmx_write_l1_tsc_offset,
.set_tdp_cr3 = vmx_set_cr3,
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-08 02:44:50 +0000