KVM: Prevent trace call into unloaded module text

(cherry picked from b82091824ee4970adf92d5cd6d57b12273171625)

Add marker_synchronize_unregister() before module unloading.
This prevents possible trace calls into unloaded module text.

Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/virt/kvm/kvm_trace.c b/virt/kvm/kvm_trace.c
index 41dcc845f78c34d65a9d13e72cc7023a8a14f142..f59874446440cab9fc51df1a55ac1a552f5c47ce 100644 (file)
--- a/virt/kvm/kvm_trace.c
+++ b/virt/kvm/kvm_trace.c
@@ -252,6 +252,7 @@ void kvm_trace_cleanup(void)
                        struct kvm_trace_probe *p = &kvm_trace_probes[i];
                        marker_probe_unregister(p->name, p->probe_func, p);
                }
+               marker_synchronize_unregister();
 
                relay_close(kt->rchan);
                debugfs_remove(kt->lost_file);