Ensure that vcpu->arch.tsc_offset continues to track the TSC offset of
the currently running guest after modifying L1's TSC offset.
Several 'write_tsc_offset' functions have been renamed to
'write_l1_tsc_offset' to clarify their behavior.
Fixes: e79f245ddec1 ("X86/KVM: Properly update 'tsc_offset' to represent the running guest")
Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/kvm/svm.c | 12 ++++++------
arch/x86/kvm/vmx.c | 19 ++++++++++---------
arch/x86/kvm/x86.c | 11 +++++------
4 files changed, 22 insertions(+), 22 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b27de80f58700..6c10fcfd78efa 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1015,7 +1015,7 @@ struct kvm_x86_ops {
bool (*has_wbinvd_exit)(void);
u64 (*read_l1_tsc_offset)(struct kvm_vcpu *vcpu);
- void (*write_tsc_offset)(struct kvm_vcpu *vcpu, u64 offset);
+ void (*write_l1_tsc_offset)(struct kvm_vcpu *vcpu, u64 offset);
void (*get_exit_info)(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2);
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index de21d5c5168b8..d268d3e229e07 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1433,7 +1433,7 @@ static u64 svm_read_l1_tsc_offset(struct kvm_vcpu *vcpu)
return vcpu->arch.tsc_offset;
}
-static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
+static void svm_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
{
struct vcpu_svm *svm = to_svm(vcpu);
u64 g_tsc_offset = 0;
@@ -1443,14 +1443,14 @@ static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
g_tsc_offset = svm->vmcb->control.tsc_offset -
svm->nested.hsave->control.tsc_offset;
svm->nested.hsave->control.tsc_offset = offset;
- } else
+ } else {
trace_kvm_write_tsc_offset(vcpu->vcpu_id,
svm->vmcb->control.tsc_offset,
offset);
-
- svm->vmcb->control.tsc_offset = offset + g_tsc_offset;
-
+ }
mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
+ svm->vmcb->control.tsc_offset = offset + g_tsc_offset;
+ vcpu->arch.tsc_offset = offset + g_tsc_offset;
}
static void avic_init_vmcb(struct vcpu_svm *svm)
@@ -7113,7 +7113,7 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.has_wbinvd_exit = svm_has_wbinvd_exit,
.read_l1_tsc_offset = svm_read_l1_tsc_offset,
- .write_tsc_offset = svm_write_tsc_offset,
+ .write_l1_tsc_offset = svm_write_l1_tsc_offset,
.set_tdp_cr3 = set_tdp_cr3,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e50beb76d846e..abb6c2a170a86 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3084,8 +3084,10 @@ static u64 vmx_read_l1_tsc_offset(struct kvm_vcpu *vcpu)
/*
* writes 'offset' into guest's timestamp counter offset register
*/
-static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
+static void vmx_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
{
+ u64 g_tsc_offset = 0;
+
if (is_guest_mode(vcpu)) {
/*
* We're here if L1 chose not to trap WRMSR to TSC. According
@@ -3093,17 +3095,16 @@ 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))
+ g_tsc_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, offset + g_tsc_offset);
+ vcpu->arch.tsc_offset = offset + g_tsc_offset;
}
/*
@@ -12929,7 +12930,7 @@ 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,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ba55be9b5c274..3c9c5b35ac54d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1545,10 +1545,9 @@ u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc)
}
EXPORT_SYMBOL_GPL(kvm_read_l1_tsc);
-static void kvm_vcpu_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
+static void kvm_vcpu_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
{
- kvm_x86_ops->write_tsc_offset(vcpu, offset);
- vcpu->arch.tsc_offset = offset;
+ kvm_x86_ops->write_l1_tsc_offset(vcpu, offset);
}
static inline bool kvm_check_tsc_unstable(void)
@@ -1657,7 +1656,7 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr)
if (!msr->host_initiated && guest_cpuid_has(vcpu, X86_FEATURE_TSC_ADJUST))
update_ia32_tsc_adjust_msr(vcpu, offset);
- kvm_vcpu_write_tsc_offset(vcpu, offset);
+ kvm_vcpu_write_l1_tsc_offset(vcpu, offset);
raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
spin_lock(&kvm->arch.pvclock_gtod_sync_lock);
@@ -1676,7 +1675,7 @@ EXPORT_SYMBOL_GPL(kvm_write_tsc);
static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu,
s64 adjustment)
{
- kvm_vcpu_write_tsc_offset(vcpu, vcpu->arch.tsc_offset + adjustment);
+ kvm_vcpu_write_l1_tsc_offset(vcpu, vcpu->arch.tsc_offset + adjustment);
}
static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment)
@@ -3078,7 +3077,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
if (kvm_check_tsc_unstable()) {
u64 offset = kvm_compute_tsc_offset(vcpu,
vcpu->arch.last_guest_tsc);
- kvm_vcpu_write_tsc_offset(vcpu, offset);
+ kvm_vcpu_write_l1_tsc_offset(vcpu, offset);
vcpu->arch.tsc_catchup = 1;
}
--
2.17.1.1185.g55be947832-goog
