On Fri, 18 Dec 2020 at 13:36, Mihai Carabas <mihai.cara...@oracle.com> wrote: > > Add pvpanic PCI device support details in docs/specs/pvpanic.txt. > > Signed-off-by: Mihai Carabas <mihai.cara...@oracle.com> > --- > docs/specs/pvpanic.txt | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/docs/specs/pvpanic.txt b/docs/specs/pvpanic.txt > index a90fbca..5ddc8df 100644 > --- a/docs/specs/pvpanic.txt > +++ b/docs/specs/pvpanic.txt > @@ -1,7 +1,7 @@ > PVPANIC DEVICE > ============== > > -pvpanic device is a simulated ISA device, through which a guest panic > +pvpanic device is a simulated device, through which a 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. > > @@ -9,6 +9,9 @@ The management app has the option of waiting for > GUEST_PANICKED events, > and/or polling for guest-panicked RunState, to learn when the pvpanic > device has fired a panic event. > > +The pvpanic device can be implemented as an ISA device (using IOPORT) or as a > +PCI device. > + > ISA Interface > ------------- > > @@ -24,6 +27,14 @@ bit 1: a guest panic has happened and will be handled by > the guest; > the host should record it or report it, but should not affect > the execution of the guest. > > +PCI Interface > +------------- > + > +The PCI interface is similar to the ISA interface except that it uses an MMIO > +address space provided by its BAR0, 2 bytes long. Any machine with a PCI > +device can enable a pvpanic device by adding '-device pvpanic-pci' to the > +command line.
Why is it 2 bytes long, when both the ISA and the ACPI interfaces are only a single byte? What size reads and writes are accepted? thanks -- PMM
