Re: [PATCH v4] x86/Hyper-V: Support for free page reporting

[Wei Liu <wei.liu@kernel.org>]

On Fri, Mar 19, 2021 at 09:30:50PM +0000, Michael Kelley wrote:
> From: Sunil Muthuswamy <sunilmut@microsoft.com>  Sent: Friday, March 19, 2021 2:21 PM
> > 
> > > What's the strategy for this flag in the unlikely event that the hypercall fails?
> > > It doesn't seem right to have hv_query_ext_cap() fail, but leave the
> > > static flag set to true.  Just move that line down to after the status check
> > > has succeeded?
> > 
> > That call should not fail in any normal circumstances. The current idea was to
> > avoid repeating the same call on persistent failure. 
> 
> OK, I can see that as a valid strategy.  And the assumption is that a failed
> hypercall would leave hv_extended_cap unmodified and hence all zeros.
> 
> I'm OK with this approach if you want to keep it.  But perhaps add a short
> comment about the intent so it doesn't look like a bug. :-)
> 

Sunil, if you can send an updated version of your patch by either
providing a comment or moving the code around, I can queue it up for
hyperv-next.

I think adding a comment is perhaps the easier thing to do.

Wei.