linux-kernel - Re: IrDA driver fails on PXA255

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20110531072650.GC21382@n2100.arm.linux.org.uk>
Date:	Tue, 31 May 2011 08:26:50 +0100
From:	Russell King - ARM Linux <linux@....linux.org.uk>
To:	David Rientjes <rientjes@...gle.com>
Cc:	Dmitry Eremin-Solenikov <dbaryshkov@...il.com>,
	Nicolas Pitre <nicolas.pitre@...aro.org>,
	linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	Eric Miao <eric.y.miao@...il.com>,
	Samuel Ortiz <samuel@...tiz.org>
Subject: Re: IrDA driver fails on PXA255

On Mon, May 30, 2011 at 10:05:38PM -0700, David Rientjes wrote:
> On Sun, 29 May 2011, Russell King - ARM Linux wrote:
> > Again, no.  This change has caused a load of previously working drivers
> > to suddenly start failing without _any_ explanation why or even warning
> > about the change.  It needs to start off as a WARN_ON() so that stuff
> > can be fixed, and then changed to a hard error.
> > 
> 
> I haven't seen a "load" of error reports where this is causing an issue, 
> maybe it is much more popular on arm?
> 
> This also isn't a hard error, admins should be able to enable 
> CONFIG_ZONE_DMA and rebuild so that the driver being loaded can get the 
> type of memory it is requesting.  Just putting a WARN_ON() doesn't provide 
> any incentive to ever get this stuff fixed.

I completely and violently disagree with your approach on this, and I'll
continue to state that I believe you are wrong until you change your
position.

Enabling CONFIG_ZONE_DMA is not a fix, it's making the problem vanish off
the radar.  It will mean that the drivers using GFP_DMA will never get
fixed up.

I don't care whether you say "it's easy enough to audit the source code" -
who's going to do that work?  If you make the problem go away the answer
to that will be NO ONE.

Change it to be a soft WARN_ON for one release.  Anything else will just
result in the problem being IGNORED.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/