Re: CONFIG_PM_TRACE corrupts RTC

[Linus Torvalds]

On Sun, 25 Jun 2006, Andrew Morton wrote:
> 
> On a Sony Vaio, after a suspend-to-disk and a resume, `hwclock' says
> 
>   The Hardware Clock registers contain values that are either invalid
>   (e.g.  50th day of month) or beyond the range we can handle (e.g.  Year
>   2095).
> 
> and after a reboot the machine takes a trip back to 1969.  Setting
> CONFIG_PM_TRACE=n prevents this.

That's how it works. It's by design. The RTC is where the trace events are 
stored, since that's the only piece of hw that reliably survives a reboot.

The help-text says:

        This enables some cheesy code to save the last PM event point in the
        RTC across reboots, so that you can debug a machine that just hangs
        during suspend (or more commonly, during resume).

Heh.

		Linus
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