linux-kernel - Re: v4.10-rc4 to v4.10-rc5: battery regression on Nokia N900

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: <20170127172039.GA2498@roeck-us.net>
Date:   Fri, 27 Jan 2017 09:20:39 -0800
From:   Guenter Roeck <linux@...ck-us.net>
To:     Zhang Rui <rui.zhang@...el.com>
Cc:     Pali Rohár <pali.rohar@...il.com>,
        Pavel Machek <pavel@....cz>, sre@...nel.org,
        kernel list <linux-kernel@...r.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
        linux-omap@...r.kernel.org, tony@...mide.com, khilman@...nel.org,
        aaro.koskinen@....fi, ivo.g.dimitrov.75@...il.com,
        patrikbachan@...il.com, serge@...lyn.com, abcloriens@...il.com,
        fabio.estevam@....com
Subject: Re: v4.10-rc4 to v4.10-rc5: battery regression on Nokia N900

On Fri, Jan 27, 2017 at 10:40:33PM +0800, Zhang Rui wrote:
> > > 
> > > If thermal zone I/F is used, we can not change it's 'type' name to
> > > be
> > > compatible with new hwmon API.
> > > 
> > You mean you can not fix the name to be compatible with libsensors.
> > 
> 
> We can try to convert it to a libsensor-compatible string, either for
> hwmon only, or for both thermal and hwmon. But this is an ABI change,
> right?

Let's go back to the basics.

Fact is that the thermal subsystem registers hwmon devices with 'name'
attributes which violate the documented hardware monitoring ABI.
I think we can consider this undisputed.

The rest is pretty much all opinion.

Is a change in a driver to stop violating a documented ABI an ABI change
or a bug fix ? In other words, does a driver violating a documented ABI
make that ABI violation part of the ABI ?

Quite interesting questions. My take is that it is a bug fix, others
apparently have the strong opinion that potential users of such an ABI
violation have priority, and that a violation of a documented ABI _does_
make this violation part of the ABI.

I'll leave it at that. I tried to make my position clear, but it appears
that I am quite alone in my opinion. With that, I'll leave it up to you to
decide how to proceed.

Guenter