Re: Regression in 2.6.27 caused by commit bfc0f59

[Thomas Gleixner <tglx@linutronix.de>]

On Sun, 31 Aug 2008, Larry Finger wrote:

> An ancient laptop of mine started throwing errors from b43legacy when I
> started using 2.6.27 on it. This has been bisected to commit bfc0f59 "x86:
> merge tsc calibration". Incidentally, I was appalled at the number of build
> errors that were found while bisecting in this region. Every commit from
> 2.6.26-rc9-00715 to at least -00719 had include errors that had to be fixed
> before it would compile. Those fixes are the only reason that the builds below
> are "dirty".
> 
> The CPU in this computer is an AMD-K6 at stepping 0c and running at 450 MHz.
> 
> The critical differences in the dmesg output between the "good" and "bad"
> results indicate a factor of 2 difference in the clock speed, and are shown
> below:

> +Clocksource tsc unstable (delta = 500037272 ns)

> -Clocksource tsc unstable (delta = 83950402 ns)

In both cases the TSC is ahead of the pm_timer, which looks like the
pm_timer is behaving strange.

Can you please disable the pm_timer (in the kernel config,
unfortunately there is no command line option for that) for a test and
provide the relevant output of demsg ?

Thanks,

	tglx