commit b4a3d965dee06d52281496bb5fd0a5cb5534b545
author Jan Kiszka <jan.kiszka@siemens.com> Tue Feb 01 22:15:43 2011 +0100
committer Marcelo Tosatti <mtosatti@redhat.com> Mon Feb 14 12:39:44 2011 -0200
tree 3d1c0bb7600ea91eea18e27530c3afa2ec41bbf7
parent aa2c364b4cf2fae4d9c8acf53ee4436ed533902d

Stop current VCPU on synchronous reset requests

If some I/O operation ends up calling qemu_system_reset_request in VCPU
context, we record this and inform the io-thread, but we do not
terminate the VCPU loop. This can lead to fairly unexpected behavior if
the triggering reset operation is supposed to work synchronously.

Fix this for TCG (when run in deterministic I/O mode) by setting the
VCPU on stop and issuing a cpu_exit. KVM requires some more work on its
VCPU loop.

[ ported from qemu-kvm ]

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

cpus.c

diff --git a/cpus.c b/cpus.c
index ab6e40e..f8a88e3 100644
--- a/cpus.c
+++ b/cpus.c
@@ -312,6 +312,10 @@
 void qemu_mutex_lock_iothread(void) {}
 void qemu_mutex_unlock_iothread(void) {}
 
+void cpu_stop_current(void)
+{
+}
+
 void vm_stop(int reason)
 {
     do_vm_stop(reason);
@@ -852,6 +856,14 @@
     qemu_notify_event();
 }
 
+void cpu_stop_current(void)
+{
+    if (cpu_single_env) {
+        cpu_single_env->stopped = 1;
+        cpu_exit(cpu_single_env);
+    }
+}
+
 void vm_stop(int reason)
 {
     QemuThread me;
@@ -863,10 +875,7 @@
          * FIXME: should not return to device code in case
          * vm_stop() has been requested.
          */
-        if (cpu_single_env) {
-            cpu_exit(cpu_single_env);
-            cpu_single_env->stop = 1;
-        }
+        cpu_stop_current();
         return;
     }
     do_vm_stop(reason);