Il 21/03/2013 09:35, Hu Tao ha scritto: > Signed-off-by: Hu Tao <hu...@cn.fujitsu.com> > --- > docs/specs/pvpanic.txt | 25 +++++++++++++++++++++++++ > 1 file changed, 25 insertions(+) > create mode 100644 docs/specs/pvpanic.txt > > diff --git a/docs/specs/pvpanic.txt b/docs/specs/pvpanic.txt > new file mode 100644 > index 0000000..761d20c > --- /dev/null > +++ b/docs/specs/pvpanic.txt > @@ -0,0 +1,25 @@ > +PVPANIC DEVICE > +============== > + > +pvpanic device is a simulated ISA device, through which guest panic > +event is sent to qemu, and a QMP event is generated. This allows > +management apps(e.g. libvirt) to be notified and respond to the > +event. > + > +pvpanic uses port 0x505 by default to receive panic event from guest. > +The port is configurable by specifying ioport property.
Please document the ISA interface too. > +pvpanic device is defined with ACPI ID "QEMU0001". To send panic > +event, guest evaluates method WRPT, specifying a byte, bit 0 set, > +as argument. Other bits are reserved. Please document RDPT too, and mention that the ACPI device will automatically refer to the right port in case it is modified. > +To use it, one will have to: > + > +1. add the device by specifying `-device pvpanic' in the qemu command > + line. As mentioned earlier, I'd like this to be the default in 1.5 and newer machine types. Paolo > +2. load pvpanic device driver in guest OS. > + > +The management app has the options of waiting for GUEST_PANICKED events, > +and/or polling for guest-panicked RunState, to learn when the pvpanic > +device has fired a panic event. >