Re: [net-next 1/2] xen-netback: add module parameter to disable ctrl-ring

["Hsu, Chiahao" <andyhsu@xxxxxxxxxx>]

Andrew Lunn 於 2021/3/21 21:29 寫道:
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> > > At the end, it will be more granular module parameter that user still
> > > will need to guess.
> > I believe users always need to know any parameter or any tool's flag before
> > they use it.
> > For example, before user try to set/clear this ctrl_ring_enabled, they
> > should already have basic knowledge about this feature,
> > or else they shouldn't use it (the default value is same as before), and
> > that's also why we use the 'ctrl_ring_enabled' as parameter name.
> To me, it seems you are fixing this problem in the wrong place. As a
> VM user in the cloud, i have no idea how the cloud provider needs the
> VM configured to allow the cloud provider to migrate the VM to
> somewhere else in the bitbarn. As the VM user, it should not be my
> problem. I would expect the cloud provider to configure the VM host to
> only expose facilities to the VM which allows it to be migrated.
'the users' I mentioned it's the cloud provider, not a VM user. Sorry 
for the confusion.
And agree with you, just wondering how the cloud provider can expose the 
facilities to the VM if there's no way to set/clr it at runtime, unless 
reconfigure kernel?  These features are enabled by default.
> This is a VM host problem, not a VM problem.
>
>       Andrew

Thanks