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Date: Wed, 22 Mar 2017 08:31:36 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>, x86@kernel.org,
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        linux-arch@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Dmitry Vyukov <dvyukov@google.com>
Subject: Re: [PATCH 4/6] x86/kasan: Prepare clear_pgds() to switch to
 <asm-generic/pgtable-nop4d.h>
Message-ID: <20170322073136.GC13904@gmail.com>
References: <20170317185515.8636-1-kirill.shutemov@linux.intel.com>
 <20170317185515.8636-5-kirill.shutemov@linux.intel.com>
 <218853b4-3498-dab9-d1e9-02caed4d9322@virtuozzo.com>
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* Andrey Ryabinin <aryabinin@virtuozzo.com> wrote:

> 
> 
> On 03/17/2017 09:55 PM, Kirill A. Shutemov wrote:
> > With folded p4d, pgd_clear() is nop. Change clear_pgds() to use
> > p4d_clear() instead.
> > 
> 
> You could probably just use set_pgd(pgd_offset_k(start), __pgd(0)); instead of pgd_clear()
> as we already do in arm64.
> It's basically pgd_clear() except it's not a nop wih p4d folded.

Makes sense. Kirill, if you agree, mind spinning a v2 patch?

Thanks,

	Ingo