Re: [Qemu-devel] qemu_power_down_request handling

[Alexander Graf]

On 16.04.2012, at 10:07, Bhushan Bharat-R65777 wrote:

> Hi All,
> 
> The "-watchdog-action shutdown" uses the monitor system_shutdown mechanism 
> but this does not actually powerdown the system. 
> 
> In code, If there is pending powerdown_request 
> (qemu_system_powerdown_request() called) then it try to raise an irq. What is 
> that irq supposed to do. Currently it in NULL pointer so does not do anything.
> 
> Code snapshot -- vl.c : main_loop_should_exit()
> 
> ....
>    if (qemu_powerdown_requested()) {
>        monitor_protocol_event(QEVENT_POWERDOWN, NULL);
>        qemu_irq_raise(qemu_system_powerdown);
>    }
> . . . .
> 
> Is the powerdown_request handling not complete?

The watchdog shutdown event is a soft power off. Imagine a PC where you press 
the power button, the OS gets notified through ACPI that it's supposed to shut 
down and shuts down the machine.

I don't know of any BookE system that has a comparable mechanism. We could 
implement it through qemu-ga and fall back to hard power off maybe?


Alex