lm_sensors

[mds@paradyne.com (Mark D. Studebaker)]

Here's my proposal.

I would like to do the 2.6.5 release as-is this week and then submit it
to Alan,
for two reasons:
- what we have in CVS is much safer for Thinkpad and 24RF08 users than
what
  is in 2.6.4; we should make it available even if it is an incremental
  improvement and not a perfect fix;
- it's much easier for tracking if we submit releases rather than CVS
stuff to Alan.

We are all agreed that what we have is not bulletproof and that we
shouldn't
claim it is. 

Let's plan on addressing whatever concerns Alan may have, together
with incorporating any further info we get from IBM, in 2.6.6.
Also in that release incorporating locking or i2c-core tweaks if
that makes sense.

As long as we are working with Alan and trying to get into 2.5 we should
try and have a release interval of about 4 weeks or less so we can be
responsive.

thoughts?

phil@netroedge.com wrote:
> 
> On Mon, Sep 09, 2002 at 11:18:44AM +0300, Ky?sti M?lkki wrote:
> >[...]
> >
> > However I do not consider current situation very satisfactory:
> >
> > 1. Blacklisting by DMI data does not catch new models beforehand.
> 
> Pam claims all current and future models will not use this chip (at
> least on Thinkpads).
> 
> > 2. IBM systems with other than PIIX4 are compromised if admin does not
> > run and/or believe sensors-detect warnings and is unaware of the issue.
> 
> Yes, there are still configurations which exist which make it possible
> for this problem to crop up again.  I worry particularly about other
> chips which may react negatively to probing.
> 
> > 3. If #1 or #2 happens, every existing client driver probing around
> > 0x54-0x57 needs a workaround. Including video4linux(2) drivers from
> > several sources, and any app using the char device.
> >
> > I think patching i2c-core to add extra Write Quick within the critical
> > section is safe and easy way to handle those issues. This leaves only
> > multi-master topologies vulnerable. What do the SMBus specs say, can a
> > laptop share SMBus with a docking station, charger etc ?
> 
> I'm wary of changing the code at quite that low of a level.  I think
> it's good we tweaked sensors-detect to do what it can to work around
> the issue.  It's also nice to have the blacklist in effect as a
> temporary measure until testing is completed.
> 
> Past that, I think we should stay out of most kernel code (with
> exception to the blacklisting code).  What we most definitely do not
> want to do is change the operation of the code to make it work in an
> unexpected way for developers (e.g. having quick writes get duplicated
> for certain addresses and such).
> 
> It's a balance between practicality and technical 'correctness'.  I'd
> like to keep things as technically correct as possible.  If a chip or
> mobo has a broken design, then it's the problem of the manufacturer.
> In practicality, it is nessesary for us to do what we can to make it
> safe for users, but I don't want to move away from having the code
> work as expected simply to work around someone else's broken hardware
> design.
> 
> Phil
> 
> --
> Philip Edelbrock -- IS Manager -- Edge Design, Corvallis, OR
>    phil@netroedge.com -- http://www.netroedge.com/~phil
>  PGP F16: 01 D2 FD 01 B5 46 F4 F0  3A 8B 9D 7E 14 7F FB 7A