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Date:   Sat, 14 May 2022 02:09:58 +0300
From:   "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To:     "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
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        "x86@kernel.org" <x86@kernel.org>,
        "ak@linux.intel.com" <ak@linux.intel.com>,
        "Lutomirski, Andy" <luto@kernel.org>
Subject: Re: [RFCv2 03/10] x86: Introduce userspace API to handle per-thread
 features
Message-ID: <20220513230958.dbxp6m3y3lnq74qb@black.fi.intel.com>
References: <20220511022751.65540-1-kirill.shutemov@linux.intel.com>
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On Fri, May 13, 2022 at 05:34:12PM +0000, Edgecombe, Rick P wrote:
> On Fri, 2022-05-13 at 16:09 +0200, Alexander Potapenko wrote:
> > > +
> > > +       /* Handle ARCH_THREAD_FEATURE_ENABLE */
> > > +
> > > +       task->thread.features |= features;
> > > +out:
> > > +       return task->thread.features;
> > 
> > Isn't arch_prctl() supposed to return 0 on success?
> 
> Hmm, good point. Maybe we'll need a struct to pass info in and out.

But values >0 are unused. I don't see why can't we use them.

-- 
 Kirill A. Shutemov