Re: PROBLEM: Suspend corrupts bios clock since 2.6.21

[Pavel Machek <pavel@ucw.cz>]

On Mon 2007-08-27 00:45:08, Rafael J. Wysocki wrote:
> On Sunday, 26 August 2007 21:38, Robert Hancock wrote:
> > Andreas Steffan wrote:
> > > Hallo everybody,
> > > 
> > > I am running fedora core 7 on my Dell latitude D810 notebook (BIOS
> > > rev A05).
> > > 
> > > Since 2.6.21 I found that suspending (to disk and to ram) corrupts
> > > the bios clock most of the time (not always). The corruption is
> > > happening during suspend. When I enter the system bios right after
> > > I switch the system back on, I find the bios clock is set to a time
> > > far in the future (many years). I guess that problem is related to
> > > the clock changes that where introduced with 2.6.21.
> > > 
> > > Please let me know if you want me to provide further information to
> > > get this problem fixed.
> > > 
> > > If there is a known quirk to work around this problem, I would
> > > really appreciate a hint.
> > > 
> > > PS: I have not yet tried 2.6.22.4-65.fc7, but the latest 2.6.22 kernel
> > > before showed the same behaviour for me.
> > 
> > Please check if PM_TRACE is enabled in your kernel configuration. It 
> > will do this intentionally.
> 
> Yes, but only if you have "1" in /sys/power/pm_trace ...

Maybe we should add printk somewhere like "pm_trace used -> I
corrupted CMOS clock for you, don't complain"... :-).
									Pavel
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