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Date:   Mon, 4 Mar 2019 16:11:14 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Steven Price <steven.price@arm.com>
Cc:     Mark Rutland <Mark.Rutland@arm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Will Deacon <will.deacon@arm.com>, linux-mm@kvack.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        "Liang, Kan" <kan.liang@linux.intel.com>,
        linux-c6x-dev@linux-c6x.org, x86@kernel.org,
        Ingo Molnar <mingo@redhat.com>,
        Mark Salter <msalter@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Aurelien Jacquiot <jacquiot.aurelien@gmail.com>,
        =?utf-8?B?SsOpcsO0bWU=?= Glisse <jglisse@redhat.com>,
        Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-arm-kernel@lists.infradead.org,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        linux-kernel@vger.kernel.org, James Morse <james.morse@arm.com>
Subject: Re: [PATCH v3 05/34] c6x: mm: Add p?d_large() definitions
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On Mon, Mar 04, 2019 at 12:01:37PM +0000, Steven Price wrote:
> On 01/03/2019 21:48, Kirill A. Shutemov wrote:
> > On Wed, Feb 27, 2019 at 05:05:39PM +0000, Steven Price wrote:
> >> walk_page_range() is going to be allowed to walk page tables other than
> >> those of user space. For this it needs to know when it has reached a
> >> 'leaf' entry in the page tables. This information is provided by the
> >> p?d_large() functions/macros.
> >>
> >> For c6x there's no MMU so there's never a large page, so just add stubs.
> > 
> > Other option would be to provide the stubs via generic headers form !MMU.
> > 
> 
> I agree that could be done, but equally the definitions of
> p?d_present/p?d_none/p?d_bad etc could be provided by a generic header
> for !MMU but currently are not. It makes sense to keep the p?d_large
> definitions next to the others.
> 
> I'd prefer to stick with a (relatively) small change here - it's already
> quite a long series! But this is certainly something that could be
> tidied up for !MMU archs.

Agreed.

-- 
 Kirill A. Shutemov