[Qemu-devel] [PATCH v12 3/5] x86: use new method to correct reset sequence

[Zhu Guihua]

During reset some devices (such as hpet, rtc) might send IRQ to APIC
which changes APIC's state from default one it's supposed to have
at machine startup time.
Fix this by resetting APIC after devices have been reset to cancel
any changes that qemu_devices_reset() might have done to its state.

Signed-off-by: Zhu Guihua <address@hidden>
---
 hw/i386/pc.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 631f89f..b414055 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1924,6 +1924,25 @@ static void pc_machine_initfn(Object *obj)
                              NULL, &error_abort);
 }
 
+static void pc_machine_reset(void)
+{
+    CPUState *cs;
+    X86CPU *cpu;
+
+    qemu_devices_reset();
+
+    /* Reset APIC after devices have been reset to cancel
+     * any changes that qemu_devices_reset() might have done.
+     */
+    CPU_FOREACH(cs) {
+        cpu = X86_CPU(cs);
+
+        if (cpu->apic_state) {
+            device_reset(cpu->apic_state);
+        }
+    }
+}
+
 static unsigned pc_cpu_index_to_socket_id(unsigned cpu_index)
 {
     unsigned pkg_id, core_id, smt_id;
@@ -1944,6 +1963,7 @@ static void pc_machine_class_init(ObjectClass *oc, void 
*data)
     mc->default_boot_order = "cad";
     mc->hot_add_cpu = pc_hot_add_cpu;
     mc->max_cpus = 255;
+    mc->reset = pc_machine_reset;
     hc->plug = pc_machine_device_plug_cb;
     hc->unplug_request = pc_machine_device_unplug_request_cb;
     hc->unplug = pc_machine_device_unplug_cb;
-- 
1.9.3