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Date: Tue, 18 Mar 2014 12:05:05 +0000
From: David Vrabel <david.vrabel@citrix.com>
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To: Andrew Morton <akpm@linux-foundation.org>
CC: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Minchan Kim <minchan@kernel.org>, Nitin Gupta <ngupta@vflare.org>,
        Jerome Marchand <jmarchan@redhat.com>, <linux-kernel@vger.kernel.org>,
        Dietmar Hahn <dietmar.hahn@ts.fujitsu.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: zram: zsmalloc calls sleeping function from atomic context
References: <20140317144358.GA374@swordfish.minsk.epam.com> <20140317160117.9bfbfdd5128d45a80f58070c@linux-foundation.org>
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On 17/03/14 23:01, Andrew Morton wrote:
> 
> OK, thanks.  David, there's our atomic unmap and there are probably
> others.  Converting a previously-atomic utility function into one which
> can sleep is going to be difficult.

I think we should drop these patches.  I think Fujitsu were doing
something particularly odd with an out-of-tree driver.

> Or can this code which vmaps 50GB be changed to unmap it in 16MB chunks
> via unmap_kernel_range(), with a cond_resched() in the loop?

This sounds like something the people from Fujitsu can explore.

David