Re: set_rtc_time() cleanup / normalization

On Tue, May 13, 2003 at 10:53:28AM +0200, Geert Uytterhoeven wrote:

On Tue, 13 May 2003, Gabriel Paubert wrote:

quoted

On Tue, May 13, 2003 at 09:52:22AM +0200, Geert Uytterhoeven wrote:

quoted

On Mon, 12 May 2003, Wolfgang Denk wrote:

quoted

I would like to find out if there is some consensus about the use  of
set_rtc_time() in the timer interrupt handler.

On m68k, we removed that part because it confused NTP. Richard Zidlicky can
probably tell more about that.

I certainly would like to know the details of this. I believe it may
be fixing the symptom rather than the cause (an NTP bug).

As far as I remember, NTP estimates the error of your RTC and uses that
estimation to correct your time if no NTP server is available, but the
estimation step fails if the kernel messes with the RTC behind NTP's back.

In this case NTP should never clear the STA_UNSYNC flag shen it
synchronized to the local clock (driver 127.127.0.0 IIRC) . The state
change from 0x41 to 0x01 should never happen for the kernel side of
the status flags, this would avoid creating the loop.

	Regards,
	Gabriel

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