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Date: Fri, 12 Oct 2018 10:58:04 -0600
From: Keith Busch <keith.busch@intel.com>
Subject: Re: [PATCHv2] mm/gup: Cache dev_pagemap while pinning pages
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To: Dan Williams <dan.j.williams@intel.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>, Linux MM <linux-mm@kvack.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Dave Hansen <dave.hansen@intel.com>, Andrew Morton <akpm@linux-foundation.org>

On Fri, Oct 12, 2018 at 09:58:18AM -0700, Dan Williams wrote:
> On Fri, Oct 12, 2018 at 4:00 AM Kirill A. Shutemov <kirill@shutemov.name> wrote:
> [..]
> > > Does this have defined behavior? I would feel better with " = { 0 }"
> > > to be explicit.
> >
> > Well, it's not allowed by the standart, but GCC allows this.
> > You can see a warning with -pedantic.
> >
> > We use empty-list initializers a lot in the kernel:
> > $ git grep 'struct .*= {};' | wc -l
> > 997
> >
> > It should be fine.
> 
> Ah, ok. I would still say we should be consistent between the init
> syntax for 'ctx' in follow_page() and __get_user_pages(), and why not
> go with '= { 0 }', one less unnecessary gcc'ism.

No problem, I'll make that happen and copy your reviews/acks into the
next patch.