0c0cc13d31
The missing functionality has been implemented now.
This reverts commit e739d1935c.
Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>
Message-Id: <20240527-pvpanic-shutdown-v8-8-5a28ec02558b@t-8ch.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
70 lines
1.9 KiB
ReStructuredText
70 lines
1.9 KiB
ReStructuredText
PVPANIC DEVICE
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==============
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pvpanic device is a simulated device, through which a guest panic
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event is sent to qemu, and a QMP event is generated. This allows
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management apps (e.g. libvirt) to be notified and respond to the event.
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The management app has the option of waiting for GUEST_PANICKED events,
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and/or polling for guest-panicked RunState, to learn when the pvpanic
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device has fired a panic event.
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The pvpanic device can be implemented as an ISA device (using IOPORT) or as a
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PCI device.
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ISA Interface
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-------------
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pvpanic exposes a single I/O port, by default 0x505. On read, the bits
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recognized by the device are set. Software should ignore bits it doesn't
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recognize. On write, the bits not recognized by the device are ignored.
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Software should set only bits both itself and the device recognize.
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Bit Definition
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~~~~~~~~~~~~~~
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bit 0
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a guest panic has happened and should be processed by the host
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bit 1
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a guest panic has happened and will be handled by the guest;
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the host should record it or report it, but should not affect
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the execution of the guest.
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bit 2
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a regular guest shutdown has happened and should be processed by the host
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PCI Interface
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-------------
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The PCI interface is similar to the ISA interface except that it uses an MMIO
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address space provided by its BAR0, 1 byte long. Any machine with a PCI bus
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can enable a pvpanic device by adding ``-device pvpanic-pci`` to the command
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line.
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ACPI Interface
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--------------
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pvpanic device is defined with ACPI ID "QEMU0001". Custom methods:
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RDPT
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~~~~
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To determine whether guest panic notification is supported.
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Arguments
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None
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Return
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Returns a byte, with the same semantics as the I/O port interface.
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WRPT
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~~~~
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To send a guest panic event.
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Arguments
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Arg0 is a byte to be written, with the same semantics as the I/O interface.
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Return
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None
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The ACPI device will automatically refer to the right port in case it
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is modified.
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