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Date:   Tue, 18 Sep 2018 18:04:20 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Rik van Riel <riel@surriel.com>, linux-kernel@vger.kernel.org,
        x86@kernel.org, Andy Lutomirski <luto@kernel.org>,
        Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        kvm@vger.kernel.org, "Jason A. Donenfeld" <Jason@zx2c4.com>
Subject: Re: [RFC PATCH 04/10 v2 ] x86/fpu: eager switch PKRU state
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On 2018-09-18 17:29:52 [+0200], Paolo Bonzini wrote:
> > I don't think it matters what the PKRU state is
> > for kernel threads, since kernel PTEs should not
> > be using protection keys anyway.
> 
> What about copy_from/to_user?

This doesn't work for a kernel thread, does it? I mean they share the
init's MM and never do copy_{from|to}_user.

> Paolo

Sebastian