[v3,0/4] Add a new -action parameter

Message

Alejandro Jimenez Dec. 11, 2020, 4:52 p.m. UTC

v3:
- Replaced the no_reboot and no_shutdown internal flags with enumerations that hold the current action
selected in case of reboot or shutdown events. The same approach is used for panic and watchdog events.
- Ensured that -no-shutdown option overrides any previously issued action panic=poweroff setting.
- Added TODO comment to add more panic actions if viable (debug, reset).
- Modified QMP command to take multiple optional args specifying actions for each event type,
and added 'allow-preconfig': true

v2:
- Replaced the individual qmp commands in patch 3/4 for a generic set-action
command that takes a RunStateAction parameter, specifying an event|action pair.
- Removed qmp_ prefix from X_set_action() functions in runstate-action.c

***

This is a follow up to the proposal to add a "-no-panicstop" option to QEMU that would allow us to
control whether the VM is paused or allowed to continue running without intervention from a management layer
when a guest panic occurs. See the inital thread and replies for details:

https://lore.kernel.org/qemu-devel/[e-mail]/

From that discussion came a request for a generic mechanism to group options like -no-shutdown, -no-reboot, etc,
that specify an action taken by QEMU in response to a guest event (reboot, shutdown, panic, and watchdog
expiration are the current options). The existing options would translate to the new option, like:

* -no-reboot --> "-action reboot=shutdown"
* -no-shutdown --> "-action shutdown=pause"

Please share any questions or comments.

Regards,
Alejandro

Alejandro Jimenez (4):
  vl: Add an -action option to respond to guest events
  vl: Add option to avoid stopping VM upon guest panic
  qmp: Allow setting -action parameters on the fly
  qtest/pvpanic: Test panic option that allows VM to continue

 MAINTAINERS                      |   2 +
 include/sysemu/runstate-action.h |  22 ++++++
 include/sysemu/sysemu.h          |   1 -
 monitor/qmp-cmds.c               |   3 +-
 qapi/run-state.json              | 149 +++++++++++++++++++++++++++++++++++++++
 qemu-options.hx                  |  25 +++++++
 softmmu/meson.build              |   1 +
 softmmu/runstate-action.c        | 142 +++++++++++++++++++++++++++++++++++++
 softmmu/vl.c                     |  64 ++++++++++++++---
 tests/qtest/pvpanic-test.c       |  26 ++++++-
 ui/sdl2.c                        |   5 +-
 11 files changed, 424 insertions(+), 16 deletions(-)
 create mode 100644 include/sysemu/runstate-action.h
 create mode 100644 softmmu/runstate-action.c

Comments

Paolo Bonzini Dec. 11, 2020, 10:23 p.m. UTC | #1

On 11/12/20 17:52, Alejandro Jimenez wrote:
> This is a follow up to the proposal to add a "-no-panicstop" option to QEMU that would allow us to
> control whether the VM is paused or allowed to continue running without intervention from a management layer
> when a guest panic occurs. See the inital thread and replies for details:
> 
> https://lore.kernel.org/qemu-devel/[e-mail]/
> 
>  From that discussion came a request for a generic mechanism to group options like -no-shutdown, -no-reboot, etc,
> that specify an action taken by QEMU in response to a guest event (reboot, shutdown, panic, and watchdog
> expiration are the current options). The existing options would translate to the new option, like:
> 
> * -no-reboot --> "-action reboot=shutdown"
> * -no-shutdown --> "-action shutdown=pause"
> 
> Please share any questions or comments.

Thanks, this looks good.

(Actually there are a bunch of changes needed for other patches that I 
have queued, but I can take care of that.  Basically, I am moving 
command line parsing from softmmu/runstate-action.c to softmmu/vl.c 
because we're trying to move all command line stuff there + in turn make 
vl.c use QMP commands as much as possible).

Paolo