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

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 16 Sep 2015 17:19:13 +0800
Zhu Guihua <zhugh.fnst@cn.fujitsu.com> wrote:

> 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 <zhugh.fnst@cn.fujitsu.com>

Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  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;