Signed-off-by: Hu Tao <hu...@cn.fujitsu.com> --- docs/specs/pvpanic.txt | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 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..d72d667 --- /dev/null +++ b/docs/specs/pvpanic.txt @@ -0,0 +1,37 @@ +PVPANIC DEVICE +============== + +pvpanic device is a simulated ISA 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. + +ISA Interface +------------- + +pvpanic uses port 0x505 to receive a panic event from the guest. On +write, bit 0 is set to indicate guest panic has happened. On read, bit +0 is set to indicate guest panic notification is supported. Remaining +bits are reserved, and should be written as 0, and ignored on read. + +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, bit 0 set to indicate guest panic + notification is supported. Other bits are reserved and + should be ignored. + +WRPT: To send a guest panic event +Arguments: Arg0 is a byte, with bit 0 set to indicate guest panic has + happened. Other bits are reserved and should be cleared. +Return: None + +The ACPI device will automatically refer to the right port in case it +is modified. -- 1.8.1.4
