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Message-ID: <1399696115.4481.48.camel@pasglop>
Subject: Re: [RFC] Heterogeneous memory management (mirror process address
 space on a device mmu).
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Sat, 10 May 2014 14:28:35 +1000
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To: Jerome Glisse <j.glisse@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, Peter Zijlstra <peterz@infradead.org>, linux-mm <linux-mm@kvack.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, linux-fsdevel <linux-fsdevel@vger.kernel.org>, Mel Gorman <mgorman@suse.de>, "H. Peter
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On Thu, 2014-05-08 at 21:26 -0400, Jerome Glisse wrote:
> Otherwise i have no other choice than to add something like mmu_notifier
> in the place where there can a be race (huge page split, cow, ...). Which
> sounds like a bad idea to me when mmu_notifier is perfect for the job.

Even there, how are you going to find a sleepable context ? All that stuff
has the PTL held.

Cheers,
Ben.



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