Subject: Re: Crash with 2.6.27-rc6 with iwlwifi
From: Johannes Berg <johannes@sipsolutions.net>
To: "Luis R. Rodriguez" <mcgrof@gmail.com>
Cc: Marcel Holtmann <holtmann@linux.intel.com>,
	Zhu Yi <yi.zhu@intel.com>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	Tomas Winkler <tomasw@gmail.com>
In-Reply-To: <43e72e890810060952p6a9a7ae5i30bdda28f1a9fab8@mail.gmail.com> (sfid-20081006_185305_022497_32408FE5)
References: <E3A88D93-F0D2-476E-B162-08687FC602E3@linux.intel.com>
	 <1221123779.2513.88.camel@debian.sh.intel.com>
	 <1221184060.11498.3.camel@californication>
	 <1221185432.6695.0.camel@californication>
	 <1223296221.15196.6.camel@johannes.berg>
	 <1223296592.11272.163.camel@violet.holtmann.net>
	 <1223296783.15196.13.camel@johannes.berg>
	 <43e72e890810060952p6a9a7ae5i30bdda28f1a9fab8@mail.gmail.com>
	 (sfid-20081006_185305_022497_32408FE5)
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Date: Mon, 06 Oct 2008 18:55:54 +0200
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On Mon, 2008-10-06 at 09:52 -0700, Luis R. Rodriguez wrote:

> > I have a different interpretation of the original issue, since afaik th=
e
> > value it was doing a BUG_ON on is a value that is only passed in by the
> > driver and copied by the ucode to the response, hence it shouldn't
> > actually crash unless the driver is passing bogus stuff in or, as it
> > seems to be the case here, the DMA programming is completely fucked and
> > the ucode just goes to write to random memory locations.
>=20
> Seems like a good enough argument to call for it to be opened up.

But there's a chance that the DMA programming being fucked up will make
it scribble over your filesystem buffers. So it's surely safer to
BUG_ON.

johannes

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