On Fri, Jan 11, 2013 at 11:24:41PM +0200, Juha Vuori wrote: > Hello, > > Yesterday, it was 417 days since our currently running z/VM was IPLed. A set > of four SLES 11.1 > guests had been alive as long as VM.
[...] > I opened a SR with Novell about zlnx011, and the conclusion was the TID > http://www.novell.com/support/kb/doc.php?id=7009834 > ... well, not exactly, but "s390x version" of it. So, I recycled zlnx011, and > plan to upgrade its > kernel soon. Thanks for bringing this to the list! The mentioned bug fix in the Novell bugzilla is http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=4cecf6d401a01d054afc1e5f605bcbfe553cb9b9 That patch is for x86 only and won't fix your problem. However we do have a similar bug in the s390 kernel code. The only difference is that it will indeed trigger after 417 days instead of 208 days. The reason is that we calculate with differences of the TOD clock register. The TOD clock wraps after appr. 143 years. So far no problem... However when converting a difference to nanoseconds we must divide the value by 4.096. Without floating point arithmetics in the kernel we do that by multiplying with 125 and afterwards dividing by 512... and there you can see when the overflow happens: 143 years / 125 = 1.114 years. And 365 days * 1.114 = 417.56 days. So, that's when we hit the overflow. We are working on a fix! Thanks again for reporting! ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
