Re: [PATCH v3 3/3] tools: introduce parameter max_wp_ram_ranges.

[Wei Liu <wei.liu2@citrix.com>]

On Tue, Feb 02, 2016 at 04:04:14PM +0800, Yu, Zhang wrote:
> Thanks for your reply, Ian.
> 
> On 2/2/2016 1:05 AM, Ian Jackson wrote:
> >Yu, Zhang writes ("Re: [Xen-devel] [PATCH v3 3/3] tools: introduce parameter max_wp_ram_ranges."):
> >>On 2/2/2016 12:35 AM, Jan Beulich wrote:
> >>>On 01.02.16 at 17:19, <yu.c.zhang@linux.intel.com> wrote:
> >>>>So, we need also validate this param in hvm_allow_set_param,
> >>>>current although hvm_allow_set_param has not performed any
> >>>>validation other parameters. We need to do this for the new
> >>>>ones. Is this understanding correct?
> >>>
> >>>Yes.
> >>>
> >>>>Another question is: as to the tool stack side, do you think
> >>>>an error message would suffice? Shouldn't xl be terminated?
> >>>
> >>>I have no idea what consistent behavior in such a case would
> >>>be - I'll defer input on this to the tool stack maintainers.
> >>
> >>Thank you.
> >>Wei, which one do you prefer?
> >
> >I think that arrangements should be made for the hypercall failure to
> >be properly reported to the caller, and properly logged.
> >
> >I don't think it is desirable to duplicate the sanity check in
> >xl/libxl/libxc.  That would simply result in there being two limits to
> >update.
> >
> 
> Sorry, I do not follow. What does "being two limits to update" mean?
> 

I can't speak for Ian, but my understanding is that if the code logic is
duplicated in several places, you need to update all of them whenever
you change the logic. But, he has expressed if this is blocker for this
series, so I will let him clarify.

Wei.