Re: 2.6.22-rc1-mm1 [cannot change thermal trip points]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi!

> > > So don't do it badly. The advantage of doing so is that you can make it 
> > > work properly, which you can't by putting it in the kernel.
> > 
> > You want stuff like critical shutdowns to work even if userspace is
> > dead.
> 
> I don't think anyone suggested putting the critical shutdown control in 
> userspace. The kernel already handles that fine.

No it does not. That is what this thread is about.

(On old xe3, critical trip point set by BIOS is ~95C, but machine dies
by hw safeguard at ~83C. Workaround is to lower critical trip point to
80C or so. Len broke this.)

> Imagine the following situation:
> 
> 1) Platform sets critical shutdown trip point to 85C
> 2) Userspace sets critical shutdown trip point to 95C
> 3) Temperature reaches 90C
> 4) Platform forces reevaluation of trip points
> 5) Entire invasion fleet is lost
> 
> How do you avoid that? Disable the ability for the platform to set trip 
> points? You're breaking the spec and potentially causing hardware 

We need to ignore trip point updates from BIOS, and we need to poll
thermals when use overrides trip points. That's expected. Plus I've
yet to see platform actually updating the trip points.

Speaking about hw damage... The broken BIOS on xe3 definitely caused
damage to its harddrive, so... we are preventing hw damage here.

(Plus, Len's patch broke user-kernel in stable series, without warning).
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux