From: Rene Rebe Date: Mon, 10 Dec 2012 21:30:08 +0000 Subject: Re: [lm-sensors] [PATCH] applesmc: add sysfs file to report OSK Message-Id: List-Id: References: <20121210145134.GA2097@hedwig.ini.cmu.edu> <20121210190905.GA24927@roeck-us.net> <20121210195414.GA642@polaris.bitmath.org> <4BC00520-E08A-43D0-AA2B-EA8154F3D160@suse.de> <4017A6C6-3074-44A5-AAAC-F4246946F151@exactcode.com> <28FE8A08-131B-4E20-BBC0-EEDDA129C1C8@suse.de> In-Reply-To: <28FE8A08-131B-4E20-BBC0-EEDDA129C1C8@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: Alexander Graf Cc: Henrik Rydberg , Guenter Roeck , "Gabriel L. Somlo" , "khali@linux-fr.org" , "linux@roeck-us.net" , "lm-sensors@lm-sensors.org" , "linux-kernel@vger.kernel.org" On 10.12.2012, at 22:24, Alexander Graf wrote: > On 10.12.2012, at 21:43, Rene Rebe wrote: >=20 >> On 10.12.2012, at 21:19, Alexander Graf wrote: >>>=20 >>> On 10.12.2012, at 20:54, Henrik Rydberg wrote: >>>=20 >>>> Hi Guenter, >>>>=20 >>>>> On Mon, Dec 10, 2012 at 09:51:35AM -0500, Gabriel L. Somlo wrote: >>>>>> The AppleSMC contains two char[32] keys, OSK0 and OSK1, which are not >>>>>> reported in the key count and index by default. These keys are used = by >>>>>> the OS X boot sequence, and normally don't matter when running Linux. >>>>>>=20 >>>>>> This patch creates a sysfs entry which reports the value of these ke= ys >>>>>> as an ASCII string, to help emulators (such as QEMU) load OS X when >>>>>> running on genuine Apple hardware. >>>>>>=20 >>>>>> Signed-off-by: Gabriel L. Somlo >>>>>> --- >>>>>>=20 >>>>>> For extra context: To boot OS X as a guest, QEMU must (among others) >>>>>> emulate the AppleSMC. To boot successfully, OS X insists on querying >>>>>> the (emulated) SMC for the value of OSK0 and OSK1. Currently, these >>>>>> values must be supplied on the QEMU command line as >>>>>>=20 >>>>>> -device applesmc,osk=3D"...concatenated values of OSK0 and OSK1..." >>>>>>=20 >>>>>> With the availability of /sys/devices/platform/applesmc.768/osk, the >>>>>> emulated QEMU AppleSMC could acquire this string directly from the >>>>>> (Apple-manufactured) host machine. >>>>> Hmm ... this is a non-hwmon attribute which doesn't really belong int= o hwmon >>>>> in the first place ... like several other attributes in the same driv= er. >>>>>=20 >>>>> So I'll leave it up to the maintainer to decide if we should accept i= t. Henrik ? >>>>=20 >>>> Indeed, the reaons against this patch are too many. I was just about >>>> to reply with the below: >>>>=20 >>>> Gabriel, >>>>=20 >>>> The OSK string seems constant accross machines, which renders the >>>> patch rather pointless, no? And even if the OSK differs between a >>>> couple of machines, the emulator could easily handle it gracefully. >>>=20 >>> The point is that the return value of the OSK is a copyrighted string, = we can not include in any other layer. The only way to make this legally sa= vvy is to read the key from the host. >>>=20 >>>>=20 >>>> There are also some technical issues with the patch below, to keep in >>>> mind for future submissions. >>>=20 >>> Sigh - most of the comments below go back to earlier review from me. He= basically had a version almost exactly like what you're asking him to do := ). Funny how code style taste differs. >>=20 >> And this is exactly the reason why I'm less and less motivated to waste = my lifetime with upstream work ... >=20 > It's nit that bad really. Gabriel can just send his earlier version again= with the ret variable name changed and then it shouldn't be an issue to ge= t it in. >=20 > Reading the key really is an important bit in creating a legally safe and= easy method to virtualize Mac OS X on Linux. Just believe us on this one := ). Sure, you do not need to convince me about that ;-) --=20 Ren=E9 Rebe, ExactCODE GmbH, Jaegerstr. 67, DE-10117 Berlin http://exactcode.com | http://t2-project.org | http://rene.rebe.de _______________________________________________ lm-sensors mailing list lm-sensors@lm-sensors.org http://lists.lm-sensors.org/mailman/listinfo/lm-sensors