Re: [PATCH V2] Add a new PIIX option to control PCI hot unplugging of devices on non-root buses

[Michael S. Tsirkin]

On Wed, Apr 29, 2020 at 06:11:20AM +0000, Ani Sinha wrote:
> 
> 
> > On Apr 29, 2020, at 10:58 AM, Michael S. Tsirkin <address@hidden> wrote:
> > 
> > o if there's a need to disable
> > just one of these, commit log needs to do a better job documenting the
> > usecase.
> 
> The use case is simple. With this feature admins will be able to do what they 
> were forced to do from Windows driver level but now at the bus level. Hence, 
> (a) They need not have access to the guest VM to change or update windows 
> driver registry settings. They can enable the same setting from admin 
> management console without any access to VM.
> (b) It is more robust. No need to mess with driver settings. Incorrect 
> settings can brick guest OS. Also no guest specific knowhow required.
> (c) It is more scalable since a single cluster wide setting can be used for 
> all VM power ons and the management plane can take care of the rest 
> automatically. No need to access individual VMs to enforce this.
> (d) I am told that the driver level solution does not persist across a 
> reboot. 
> 
> Ani

Looks like disabling both plug and unplug would also address these needs.

-- 
MST