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Date: Fri, 29 May 2015 14:48:55 +0200
From: Hans Petter Selasky <hps@selasky.org>
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To: Luigi Rizzo <rizzo@iet.unipi.it>, 
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CC: Giuseppe Lettieri <g.lettieri@iet.unipi.it>
Subject: Re: per file descriptor device driver data ?
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On 05/29/15 14:24, Luigi Rizzo wrote:
> Our current design uses devfs_set_cdevpriv() during the open()
> handler, but for some reason a subsequent devfs_get_cdevpriv(p)
> returns *p = NULL in additional threads created by the process
> that did the open().

Hi,

Are you sure it is the same file handle passed around, that the FD's 
were not cloned? The devfs_set_cdevpriv() is per "struct file" in the 
kernel from my knowledge.

--HPS