diff options
| -rw-r--r-- | arch/x86/kvm/x86.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8e77e61d4fbd..462a5cd6ac4a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3733,7 +3733,13 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) u32 msr = msr_info->index; u64 data = msr_info->data; - if (msr && msr == vcpu->kvm->arch.xen_hvm_config.msr) + /* + * Do not allow host-initiated writes to trigger the Xen hypercall + * page setup; it could incur locking paths which are not expected + * if userspace sets the MSR in an unusual location. + */ + if (msr && msr == vcpu->kvm->arch.xen_hvm_config.msr && + !msr_info->host_initiated) return kvm_xen_write_hypercall_page(vcpu, data); switch (msr) { |