[Qemu-devel] [RFC PATCH 0/5] FAULT INJECTION FRAMEWORK

[Damien Hedde]

Hi all,

This series adds a python framework aiming to provide some ways to do fault
injection in a running vm. In its current state, it allows to easily interact
with memory, change gpios and qom properties.

The framework consists in a python script based on the qmp existing module
which allows to interact with the vm.

The series introduces a QMP command to schedule some virtual-clock-time-based
notifications. The notification is sent back to the python framework and can
be used to build time-driven fault scenario.

Additionaly the series adds some new QMP commands:

Commands are added to read/write memory or memory-mapped registers. Arguments
are similar to the existing [p]memsave commands.

A command is added to set a value to a qdev gpio.

Here's is a simple visual example which inject characters on the uart output
of the zynq platform:
$ # qemu must have been launched with -qmp unix:/tmp/qmpsock,server
$ # create the python framework object
$ import fault_injection
$ inj = fault_injection.FaultInjectionFramework("/tmp/qmpsock", 0)
$
$ # function which display a 'X' to the first uart
$ # it access directly the register using the physical address
$ def cb():
$   inj.write_pmem(0xe0000030,4, 88)
$
$ # schedule the function on a notification in 10s
$ inj.notify(10 * 1000 * 1000 * 1000, cb, True)
$
$ # handle one notification
$ inj.run_once()

The framework has been tested using python 2, on qemu running xilinx_zynq or
virt arm machines.

The series is organised as follows. Patches 1 and 2 adds the memory qmp and
gpio commands. Patch 3 adds the notification mechanism. Patches 4 and 5 add
a python helper module and some documention.

Thanks to the Xilinx's QEMU team who sponsored this work.

Damien Hedde (5):
  introduce [p]mem(read|write) qmp commands
  introduce a qmp command to set gpios
  add qmp time-notify event triggering system
  fault_injection: introduce Python scripting framework
  docs: add fault injection framework documentation

 cpus.c                         | 126 +++++++++++++++
 docs/fault_injection.txt       | 149 ++++++++++++++++++
 monitor/Makefile.objs          |   1 +
 monitor/qmp-cmd-time-notify.c  | 116 ++++++++++++++
 monitor/qmp-cmds.c             |  30 ++++
 monitor/trace-events           |   4 +
 qapi/misc.json                 | 196 +++++++++++++++++++++++
 scripts/qmp/fault_injection.py | 278 +++++++++++++++++++++++++++++++++
 8 files changed, 900 insertions(+)
 create mode 100644 docs/fault_injection.txt
 create mode 100644 monitor/qmp-cmd-time-notify.c
 create mode 100644 scripts/qmp/fault_injection.py

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2.22.0