When running nested we need to touch the l1 guests
tsc_offset. Otherwise changes will be lost or a wrong value
be read.

Signed-off-by: Joerg Roedel <[email protected]>
---
 arch/x86/kvm/svm.c |   23 +++++++++++++++++------
 1 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 84c2c78..e193cf9 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2059,10 +2059,14 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, unsigned 
ecx, u64 *data)
 
        switch (ecx) {
        case MSR_IA32_TSC: {
-               u64 tsc;
+               u64 tsc_offset;
 
-               rdtscll(tsc);
-               *data = svm->vmcb->control.tsc_offset + tsc;
+               if (is_nested(svm))
+                       tsc_offset = svm->nested.hsave->control.tsc_offset;
+               else
+                       tsc_offset = svm->vmcb->control.tsc_offset;
+
+               *data = tsc_offset + native_read_tsc();
                break;
        }
        case MSR_K6_STAR:
@@ -2148,10 +2152,17 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, unsigned 
ecx, u64 data)
 
        switch (ecx) {
        case MSR_IA32_TSC: {
-               u64 tsc;
+               u64 tsc_offset = data - native_read_tsc();
+               u64 g_tsc_offset = 0;
+
+               if (is_nested(svm)) {
+                       g_tsc_offset = svm->vmcb->control.tsc_offset -
+                                      svm->nested.hsave->control.tsc_offset;
+                       svm->nested.hsave->control.tsc_offset = tsc_offset;
+               }
+
+               svm->vmcb->control.tsc_offset = tsc_offset + g_tsc_offset;
 
-               rdtscll(tsc);
-               svm->vmcb->control.tsc_offset = data - tsc;
                break;
        }
        case MSR_K6_STAR:
-- 
1.6.3.3


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