mirror of
https://github.com/xemu-project/xemu.git
synced 2024-11-27 05:20:50 +00:00
cb2cc20692
Add pvpanic PCI device support details in docs/specs/pvpanic.txt. Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
55 lines
1.8 KiB
Plaintext
55 lines
1.8 KiB
Plaintext
PVPANIC DEVICE
|
|
==============
|
|
|
|
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.
|
|
|
|
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
|
|
-------------
|
|
|
|
pvpanic exposes a single I/O port, by default 0x505. On read, the bits
|
|
recognized by the device are set. Software should ignore bits it doesn't
|
|
recognize. On write, the bits not recognized by the device are ignored.
|
|
Software should set only bits both itself and the device recognize.
|
|
|
|
Bit Definition
|
|
--------------
|
|
bit 0: a guest panic has happened and should be processed by the host
|
|
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, 1 byte long. Any machine with a PCI bus
|
|
can enable a pvpanic device by adding '-device pvpanic-pci' to the command
|
|
line.
|
|
|
|
ACPI Interface
|
|
--------------
|
|
|
|
pvpanic device is defined with ACPI ID "QEMU0001". Custom methods:
|
|
|
|
RDPT: To determine whether guest panic notification is supported.
|
|
Arguments: None
|
|
Return: Returns a byte, with the same semantics as the I/O port
|
|
interface.
|
|
|
|
WRPT: To send a guest panic event
|
|
Arguments: Arg0 is a byte to be written, with the same semantics as
|
|
the I/O interface.
|
|
Return: None
|
|
|
|
The ACPI device will automatically refer to the right port in case it
|
|
is modified.
|