Re: [PATCH 2/2] Drivers: hv: vmbus: Display nothing in sysfs if monitor_allocated not set

From: Kimberly Brown
Date: Mon Feb 11 2019 - 10:16:03 EST


On Fri, Feb 08, 2019 at 02:32:09PM -0800, Stephen Hemminger wrote:
> On Fri, 8 Feb 2019 05:01:12 -0500
> Kimberly Brown <kimbrownkd@xxxxxxxxx> wrote:
>
> You are right, the current behavior is broken.
> It would be good to add a description of under what conditions
> monitor is not used. Is this some part of a project emulating
> Hyper-V?
>

I'm not sure which conditions determine whether the monitor mechanism is
used. I've searched the Hypervisor TLFS, and I couldn't find any
information. If you have any suggestions for where I can find this
information, please let me know.

No, I'm not working on a project emulating Hyper-V.


>
> > +
> > + if (!hv_dev->channel->offermsg.monitor_allocated)
> > + return sprintf(buf, "\n");
>
> If monitor is not used, why not return an error instead of empty
> data. Any program (or user) would have to handle that already.

I think that returning an error instead is fine. I'll make this change
in the next version of the patch.