x86/hvm: fix non-onchangeonly CR write events logic

hvm_event_crX() already returns a bool_t to tell us whether an
event will be sent out or not, so the extra check that value != old
is not only useless, but also prevents non-onchangeonly events from
being sent.

Signed-off-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>

diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index c9576109d398807a73f9cb3c6e2812f448d38e0a..707ad86d11f2231fd5cdc92c439b73466cfe84f1 100644 (file)
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -3368,8 +3368,7 @@ int hvm_set_cr0(unsigned long value, bool_t may_defer)
     }
 
     if ( may_defer && unlikely(currad->monitor.write_ctrlreg_enabled &
-                               monitor_ctrlreg_bitmask(VM_EVENT_X86_CR0)) &&
-         value != old_value )
+                               monitor_ctrlreg_bitmask(VM_EVENT_X86_CR0)) )
     {
         ASSERT(currad->event_write_data != NULL);
 
@@ -3472,8 +3471,7 @@ int hvm_set_cr3(unsigned long value, bool_t may_defer)
     struct arch_domain *currad = &v->domain->arch;
 
     if ( may_defer && unlikely(currad->monitor.write_ctrlreg_enabled &
-                               monitor_ctrlreg_bitmask(VM_EVENT_X86_CR3)) &&
-         value != old )
+                               monitor_ctrlreg_bitmask(VM_EVENT_X86_CR3)) )
     {
         ASSERT(currad->event_write_data != NULL);
 
@@ -3546,8 +3544,7 @@ int hvm_set_cr4(unsigned long value, bool_t may_defer)
     }
 
     if ( may_defer && unlikely(currad->monitor.write_ctrlreg_enabled &
-                               monitor_ctrlreg_bitmask(VM_EVENT_X86_CR4)) &&
-         value != old_cr )
+                               monitor_ctrlreg_bitmask(VM_EVENT_X86_CR4)) )
     {
         ASSERT(currad->event_write_data != NULL);