On Thu, Feb 16, 2012 at 9:27 AM, Don Zickus <dzickus at redhat.com> wrote: > So I think I figured it out. ?I went through and commented out code in > disable_local_APIC until I narrowed it down to the piece of code that > needs to be disabled for it to work. > > Surprise, surprise... its LVTPC or perf! :-) ?Actually it is the > nmi_watchdog which uses perf. ?My theory is NMIs are not disabled and one > is generated by the local apic during decompression (just bad timing) and > *splat*. > > Yinghai, you can probably prove this by > > echo 0 > /proc/sys/kernel/nmi_watchdog > > then do your kdump crash test. yes. that will make kdump crash working. Yinghai