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Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c12
1 files changed, 10 insertions, 2 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index dff08e527ec7..54f73b6a006b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -754,14 +754,22 @@ static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock)
{
- static int version;
+ int version;
+ int r;
struct pvclock_wall_clock wc;
struct timespec boot;
if (!wall_clock)
return;
- version++;
+ r = kvm_read_guest(kvm, wall_clock, &version, sizeof(version));
+ if (r)
+ return;
+
+ if (version & 1)
+ ++version; /* first time write, random junk */
+
+ ++version;
kvm_write_guest(kvm, wall_clock, &version, sizeof(version));