“Apparently a bug in GPSD, the daemon responsible for deriving time from the GPS system, is going to trigger on October 24, 2021, jumping the time back to March of 2002,” writes Slashdot reader suutar. “There’s a fix that’s been committed since August, but of course not everything is up to date.” ZDNet’s Steven J. Vaughan-Nichols writes: This will be ugly. Or, as Stephen Williams, who uncovered the bug put it, “I have a feeling that there will be some ‘interesting moments’ in the early morning when a bunch of the world’s stratum 1 NTP servers using GPSD take the long strange trip back to 2002.” GPSD maintainer Gary E. Miller has acknowledged the problem, and a fix has been made to the code. To be exact, the fix is in August 2021’s GPSD 3.23 release. So, what’s the problem if the fix is already in?
Well, there are two problems. First, it won’t be backported to previous releases. If you’re still using an older version, you may be out of luck. Second, as Miller observed, not all distros “pick up GPSD updates or upstream their patches. [This] is a very sore spot with me.” So, just because your operating system is up to date does not mean that it will have the necessary GPSD fix. Miller suggests that you check it and do it yourself: “I [am] gonna fall back on Greg K_H’s dictum: All users must update.”
Oh, wondering what the mysterious root cause of all this commotion GPS Week Rollover? It’s a legacy GPS problem. The GPS signal GPS week number uses a 10-bit code with a maximum value of 1,023. This means every 19.7 years; the GPS week number rolls over to zero. Or, as Miller noted, “This code is a 1024 week time warp waiting to happen.” So, check your systems now for this problem. And, if, like most of us, you’re relying on someone upstream from you for the correct time, check with them to make sure they’ve taken care of this forthcoming trouble.
Read more of this story at Slashdot.