[libvirt] [PATCH] qemu: don't set fake reboot if it will not be used

[John Ferlan]

On 06/30/2016 05:42 AM, Nikolay Shirokovskiy wrote:
> The use case is similar to e2b86f580. First call shutdown with
> reboot semantics in agent mode. As a result fake reboot flag is set.
> Next issue shutdown from guest and you will get reboot due to fake
> reboot flag set.
> 
> Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy at virtuozzo.com>
> ---
>  src/qemu/qemu_driver.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 

In qemuDomainShutdownFlags 'isReboot' is initialized to 'false';
whereas, in qemuDomainReboot it's initialized to 'true'. Both routines
can change the value based on the domain settings.

For shutdown, it's what the domain has set for "onPoweroff" - we'll
request a reboot.

Trying to figure out what I'm missing from your commit message and what
I'm reading in the code. By moving this from where it is now to be
cleared unless domain setting onPoweroff dictates a restart to a more
specific spot where the value only changes if the Agent isn't used or
fails (or perhaps from the old non flags qemuDomainShutdown API), you
could conceivably "leave" the setting as is for Agent powerdown.

This also seems to undo commit id '8be502fd' - ok your placement is a
bit different, but nonetheless there's an ominous looking commit message
there.

Also of note is in the Reboot code there's some #ifdef's w/ YAJL, but
those aren't present for the shutdown code... That's not part of this
bug, but perhaps someone with more libvirt history can answer...

Maybe the "shared" code should be combined in some way...

John
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index 61d184b..f9562bd 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -1997,8 +1997,6 @@ static int qemuDomainShutdownFlags(virDomainPtr dom, unsigned int flags)
>          useAgent = false;
>      }
>  
> -    qemuDomainSetFakeReboot(driver, vm, isReboot);
> -
>      if (useAgent) {
>          qemuDomainObjEnterAgent(vm);
>          ret = qemuAgentShutdown(priv->agent, agentFlag);
> @@ -2018,6 +2016,7 @@ static int qemuDomainShutdownFlags(virDomainPtr dom, unsigned int flags)
>              goto endjob;
>          }
>  
> +        qemuDomainSetFakeReboot(driver, vm, isReboot);
>          qemuDomainObjEnterMonitor(driver, vm);
>          ret = qemuMonitorSystemPowerdown(priv->mon);
>          if (qemuDomainObjExitMonitor(driver, vm) < 0)
>