The guest may access the pv vcpu_time_info immediately after
VCPUOP_register_vcpu_info. This is to borrow the idea of
VCPUOP_register_vcpu_time_memory_area, where the
force_update_vcpu_system_time() is called immediately when the new memory
area is registered.
Otherwise, we may observe clock drift at the VM side if the VM accesses
the clocksource immediately after VCPUOP_register_vcpu_info().
Cc: Joe Jin <joe....@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zh...@oracle.com>
---
xen/common/domain.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/xen/common/domain.c b/xen/common/domain.c
index 40d67ec342..c879f6723b 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -1695,6 +1695,8 @@ long do_vcpu_op(int cmd, unsigned int vcpuid,
XEN_GUEST_HANDLE_PARAM(void) arg)
rc = map_vcpu_info(v, info.mfn, info.offset);
domain_unlock(d);
+ force_update_vcpu_system_time(v);
+
break;
}
--
2.17.1
