linux-kernel - Re: [PATCH] mfd: wm5102: Mark register 0x19 readable

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] [day] [month] [year] [list]

Message-ID: <20140310172947.GU28112@sirena.org.uk>
Date:	Mon, 10 Mar 2014 17:29:47 +0000
From:	Mark Brown <broonie@...nel.org>
To:	Lars-Peter Clausen <lars@...afoo.de>
Cc:	Charles Keepax <ckeepax@...nsource.wolfsonmicro.com>,
	Lee Jones <lee.jones@...aro.org>,
	patches@...nsource.wolfsonmicro.com,
	Samuel Ortiz <sameo@...ux.intel.com>,
	linaro-kernel@...ts.linaro.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] mfd: wm5102: Mark register 0x19 readable

On Mon, Mar 10, 2014 at 06:17:22PM +0100, Lars-Peter Clausen wrote:
> On 03/10/2014 06:05 PM, Charles Keepax wrote:

> >WRITE_SEQUENCER_CTRL_3, seems we should add that in since it is
> >required for that 5102 boot stuff. Slightly confused as to how
> >that ever worked without the register being readable, but guess
> >it has been a while since I have fired up 5102 on mainline.

> Presumably this change triggered it:

> http://git.kernel.org/cgit/linux/kernel/git/broonie/regmap.git/commit/?h=topic/core&id=d4807ad2c4c0e17b6f00e3be9492c81de0804f40

Indeed.  Now that I think about it there's another bug lying underneath
too - the register isn't marked as volatile so it'll only actually be
being read on first read.  For some reason that check is only done on
probe so it's got no impact but it seems it's asking for future
breakage.

Download attachment "signature.asc" of type "application/pgp-signature" (837 bytes)