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Date: Tue, 04 Aug 2009 11:18:51 +0200
From: Brice Goglin <Brice.Goglin@inria.fr>
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To: Hugh Dickins <hugh.dickins@tiscali.co.uk>
CC: Leon Woestenberg <leon.woestenberg@gmail.com>,
       linux-kernel@vger.kernel.org
Subject: Re: get_user_pages() on an mmap()ed file allowed? What to do if 0
 <  get_user_pages(..., nr_pages, ...) < nr_pages?
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Hugh Dickins wrote:
>> - what should a driver do when get_user_pages() returns less pages
>> than requested?
> 
> Probably put_page the pages gotten then report the surprise;
> perhaps, before putting the pages gotten, try get_user_pages
> on the next alone, to see what error code is returned for that.

I wonder if we should change get_user_pages to store ERR_PTR(ret)
in page[i] when it fails to get page #i.

Brice