And also kernel 2.6.32 has a bug.
Xeon bug + kernel bug = hung after warm reboot (or kexec) after 208.5 days
since booting. So, administrators should shutdown it once at all, then
boot it again because “shutdown -r” causes hang up.
Red Hat Enterprise Linux 6.1 (kernel-2.6.32-131.26.1.el6 and newer)
Red Hat Enterprise Linux 6.2 (kernel-2.6.32-220.4.2.el6 and newer)
Red Hat Enterprise Linux 6.3 (kernel-2.6.32-279 series)
Red Hat Enterprise Linux 6.4 (kernel-2.6.32-358 series)
Any Intel® Xeon® E5, Intel® Xeon® E5 v2, or Intel® Xeon® E7 v2 series processor
From 9993bc635d01a6ee7f6b833b4ee65ce7c06350b1 Mon Sep 17 00:00:00 2001
From: Salman Qazi <firstname.lastname@example.org>
Date: Sat, 10 Mar 2012 00:41:01 +0000
Subject: sched/x86: Fix overflow in cyc2ns_offset
When a machine boots up, the TSC generally gets reset. However,
when kexec is used to boot into a kernel, the TSC value would be
carried over from the previous kernel. The computation of
cycns_offset in set_cyc2ns_scale is prone to an overflow, if the
machine has been up more than 208 days prior to the kexec. The
overflow happens when we multiply *scale, even though there is
enough room to store the final answer.
We fix this issue by decomposing tsc_now into the quotient and
remainder of division by CYC2NS_SCALE_FACTOR and then performing
the multiplication separately on the two components.
Refactor code to share the calculation with the previous
fix in __cycles_2_ns().