On Wed, 19 Feb 2003, davidsen@tmr.com wrote:
> set_rtc_mmss: can't update from 5 to 55
>
> I used to get this message in early 4.5.5x kernels, and there was some
> discussion which I can't easily track right now, then it went away. This
> system was up for 25 days on 2.5.59+patches, and the console showed none
> of these since boot.
My bad, see below, I just lucked out not to boot at the wrong time, and
after that the problem doesn't happen (or is unlikely).
> I just built 2.5.61-ac1 and booted. The good news is that it is up and
> looks reasonably stable (rebuilt the kernel). Bad news is that this
> message is coming out often enough to make the console hard to use.
>
> No details, I assume that whatever fixed this before will fix it again,
> just so someone knows it is happening again.
Okay, now I see what's happening. In arch/i386/kernel/time.c, the routine
is far more limited than the comments admit. And the code tests for a 30
minute change, while the comments only say 15.
Since the code change is complex, requiring backing the time over an hour
and potentially date boundary, I just patch the comment to admit what's
happening.
--- time.c.ORIG Thu Feb 20 00:10:33 2003
+++ time.c Thu Feb 20 00:32:37 2003
@@ -169,7 +169,10 @@
* since we're only adjusting minutes and seconds,
* don't interfere with hour overflow. This avoids
* messing with unknown time zones but requires your
- * RTC not to be off by more than 15 minutes
+ * RTC not to be off by more than 30 minutes. It also
+ * will fail to set back the minutes over an hour boundary,
+ * say from 1 to 59, even though that's only 2 minutes,
+ * to avoid being off by an hour.
*/
real_seconds = nowtime % 60;
real_minutes = nowtime / 60;
-- bill davidsen, CTO TMR Associates, Inc <davidsen@tmr.com> Having the feature freeze for Linux 2.5 on Hallow'een is appropriate, since using 2.5 kernels includes a lot of things jumping out of dark corners to scare you.- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sun Feb 23 2003 - 22:00:28 EST