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Date:   Tue, 20 Dec 2022 15:24:46 +0800
From:   Chao Peng <chao.p.peng@linux.intel.com>
To:     Borislav Petkov <bp@alien8.de>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
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        Naoya Horiguchi <naoya.horiguchi@nec.com>,
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Subject: Re: [PATCH v10 2/9] KVM: Introduce per-page memory attributes
Message-ID: <20221220072446.GB1724933@chaop.bj.intel.com>
Reply-To: Chao Peng <chao.p.peng@linux.intel.com>
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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