RE: [PATCH v2] Add AutoReboot capability

[Paul Durrant <xadimgnik@xxxxxxxxx>]

> -----Original Message-----
> From: win-pv-devel <win-pv-devel-bounces@xxxxxxxxxxxxxxxxxxxx> On Behalf Of 
> Owen Smith
> Sent: 15 December 2020 16:29
> To: win-pv-devel@xxxxxxxxxxxxxxxxxxxx
> Cc: Owen Smith <owen.smith@xxxxxxxxxx>
> Subject: [PATCH v2] Add AutoReboot capability
> 
> Setting HKLM\System\CCS\Services\xenbus_monitor\AutoReboot to non-zero
> will allow xenbus_monitor to trigger a reboot when another driver
> requests a reboot. AutoReboot is set to the maximum number of reboots
> to perform. Auto reboots display a message with a 60 second timeout.
> 
> This setting can be used to allow headless/unmonitored VMs to complete
> the neccessary number of reboots to return to PV disks/networks. Without
> this capability its possible to update the driver on a parent device,
> which may prompt for a reboot. After this reboot, its likely that
> emulated devices are used whilst drivers are rebound to the device
> nodes. This can leave headless/unmonitored VMs in a state where emulated
> devices are in use with a pending reboot. If network settings have been
> changed for PV devices (e.g. static IP addressing), then the VM may not
> be accessible over RDP or similar connections.
> 
> RebootCount is cleared when no pending required reboots are detected.
> 
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxxx>

Acked-by: Paul Durrant <paul@xxxxxxx>