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Date: Thu, 26 Jan 2017 07:44:39 -0800
From: Matthew Wilcox <willy@infradead.org>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>,
        Andreas Dilger <adilger.kernel@dilger.ca>, Jan Kara <jack@suse.com>,
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Subject: Re: [PATCHv6 06/37] thp: handle write-protection faults for file THP
Message-ID: <20170126154439.GB20495@bombadil.infradead.org>
References: <20170126115819.58875-1-kirill.shutemov@linux.intel.com>
 <20170126115819.58875-7-kirill.shutemov@linux.intel.com>
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On Thu, Jan 26, 2017 at 02:57:48PM +0300, Kirill A. Shutemov wrote:
> For filesystems that wants to be write-notified (has mkwrite), we will
> encount write-protection faults for huge PMDs in shared mappings.
> 
> The easiest way to handle them is to clear the PMD and let it refault as
> wriable.

... of course, the filesystem could implement ->pmd_fault, and then it
wouldn't hit this case ...