linux-kernel - Re: [PATCH] mmc: host: omap_hsmmc: add a verbose print to enable CONFIG_REGULATOR

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: <20160115091421.GD5783@n2100.arm.linux.org.uk>
Date:	Fri, 15 Jan 2016 09:14:21 +0000
From:	Russell King - ARM Linux <linux@....linux.org.uk>
To:	Sebastian Reichel <sre@...nel.org>
Cc:	Kishon Vijay Abraham I <kishon@...com>,
	Ulf Hansson <ulf.hansson@...aro.org>,
	ivo.g.dimitrov.75@...il.com, aaro.koskinen@....fi,
	Tony Lindgren <tony@...mide.com>, nsekhar@...com,
	khilman@...nel.org, linux-mmc@...r.kernel.org,
	linux-kernel@...r.kernel.org, NeilBrown <neilb@...e.de>,
	pavel@....cz, pali.rohar@...il.com, linux-omap@...r.kernel.org,
	patrikbachan@...il.com, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH] mmc: host: omap_hsmmc: add a verbose print to enable
 CONFIG_REGULATOR_PBIAS

On Thu, Jan 14, 2016 at 11:40:25PM +0100, Sebastian Reichel wrote:
> On Thu, Jan 14, 2016 at 05:25:49PM +0000, Russell King - ARM Linux wrote:
> > There are very good reasons not to do this: that will result in
> > configurations where MMC_OMAP_HS was set but without REGULATOR_PBIAS
> > ending up with MMC_OMAP_HS being disabled.  That doesn't help the
> > root problem, which is "why has the kernel boot regressed for my
> > previous working configuration?"
> > 
> > The solution proposed here adds a message to the boot which points
> > out fair and square what needs to be done to rectify the boot
> > failure.  Adding a dependency just brings up the question "where
> > has my MMC driver gone?"
> 
> The best thing would be to have no regression. Just printing a
> message means I have to build another kernel. But more importantly
> the message may not be visible by the user - e.g. if the display has
> not yet been initialized.

I agree in principle, but that's not possible here (see Tony's mails
on why the PBIAS stuff needs to be optional.)  I'd agree with changing
the Kconfig if PBIAS were a hard and fast requirement, but it isn't.

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.