linux-kernel - Re: [PATCH] ASoC: fsl_asrc: Add reg_defaults for regmap to fix kernel dump

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: <20141028104742.GP18557@sirena.org.uk>
Date:	Tue, 28 Oct 2014 10:47:42 +0000
From:	Mark Brown <broonie@...nel.org>
To:	Nicolin Chen <nicoleotsuka@...il.com>
Cc:	linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
	alsa-devel@...a-project.org
Subject: Re: [PATCH] ASoC: fsl_asrc: Add reg_defaults for regmap to fix
 kernel dump

On Mon, Oct 27, 2014 at 09:26:26PM -0700, Nicolin Chen wrote:
> On Tue, Oct 28, 2014 at 12:19:04AM +0000, Mark Brown wrote:

> > It's not a bug, it's not reasonable to default allocations to atomic and
> > we can't really tell what context we're in.  Anything used inside a
> > heavily locked path should either have a default provided or arrange for
> > a prior write to set up the cache.

> I've a little trouble to understand the prior write over here. Inside my
> probe() there's a register_init() call which has a set of regmap_write().
> And then the first regmap_write() results the dump. Does that mean this
> regmap_write() isn't prior write? If so, how should I do if not setting

Oh, bother.  We fixed things so that we're now always running with the
spinlock held...  never mind.

> default values here -- Some IPs may have default value 0 for registers.
> And this would make reg_defaults tedious since there's nothing special
> to assign.

Write a small script then, or a little bit of code to create the
defaults dynamically.

> And actually I remember I haven't seen any dump when I sent the initial
> patch for the whole ASRC driver but it manifested last month. I thought
> it might be a partially-merging issue and it would be fixed after merge
> window's done.....

Nothing has changed here for a while as far as I remember.

Download attachment "signature.asc" of type "application/pgp-signature" (474 bytes)