Re: [PATCH v10 2/9] KVM: Introduce per-page memory attributes

From: Chao Peng
Date: Tue Dec 20 2022 - 02:30:19 EST


On Mon, Dec 19, 2022 at 11:17:22AM +0100, Borislav Petkov wrote:
> On Mon, Dec 19, 2022 at 04:15:32PM +0800, Chao Peng wrote:
> > Tamping down with error number a bit:
> >
> > if (attrs->flags)
> > return -ENXIO;
> > if (attrs->attributes & ~supported_attrs)
> > return -EOPNOTSUPP;
> > if (!PAGE_ALIGNED(attrs->address) || !PAGE_ALIGNED(attrs->size) ||
> > attrs->size == 0)
> > return -EINVAL;
> > if (attrs->address + attrs->size < attrs->address)
> > return -E2BIG;
>
> Yap, better.
>
> I guess you should add those to the documentation of the ioctl too
> so that people can find out why it fails. Or, well, they can look
> at the code directly too but still... imagine some blurb about
> user-friendliness here...

Thanks for reminding. Yes KVM api doc is the right place to put these
documentation in.

Thanks,
Chao
>
> :-)
>
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette