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From: David Chow <davidchow@rcn.com.hk>
To: unlisted-recipients:; (no To-header on input)@localhost.localdomain
Cc: "Richard B. Johnson" <root@chaos.analogic.com>,
	linux-kernel@vger.kernel.org
Subject: Re: EFAULT from file read.
Date: Wed, 19 Sep 2001 18:24:47 +0800	[thread overview]
Message-ID: <3BA8726F.CC5FA2AD@rcn.com.hk> (raw)
In-Reply-To: <Pine.GSO.4.21.0109180900320.25323-100000@weyl.math.psu.edu>

Alexander Viro ¼g¹D¡G
> 
> On Tue, 18 Sep 2001, Richard B. Johnson wrote:
> 
> > File I/O requires a process context. Your file descriptor means
> > nothing unless associated with the process that opened the file.
> 
> It fscking doesn't.  He had clearly said that he calls file->f_op->read(),
> which has nothing whatsofuckingever to descriptors.  Sod off and don't
> return until you learn to read.
> 
> As for the original question - grep fro set_fs and you'll see what to
> do (basically, set_fs(KERNEL_DS) before the call of ->read() and restore
> afterwards).

Problem solved by calling dummy=set_fs(KERNEL_DS) . But remember to call
set_fs(dummy) to restore after the read.

regards,

David

      reply	other threads:[~2001-09-19 10:28 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-09-18  9:16 EFAULT from file read David Chow
2001-09-18 12:53 ` Richard B. Johnson
2001-09-18 13:04   ` Alexander Viro
2001-09-19 10:24     ` David Chow [this message]

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