RE: [V4 PATCH 4/4] x86/apic: Introduce noextnmi boot option

From: æåèå / KAWAIïHIDEHIRO
Date: Thu Oct 01 2015 - 06:24:29 EST


> On Thu, Oct 01, 2015 at 07:01:50AM +0000, æåèå / KAWAIïHIDEHIRO wrote:
> > I suppose that a sever which uses this feature will equip a BMC
> > and BMC mandatorily supports hard reset command for the server.
> > If the HA clustering software detects no response from the server
> > after relatively long timeout, it might want to insert hard reset
> > to the server by IPMI over LAN.
>
> So why doesn't the capture kernel *automatically* ignore external NMIs,
> without a cmdline option?
>
> Before it starts capturing, it says: "I'm starting capturing and am
> ignoring external NMIs from now on."

But how do we check if the starting kernel is a dump capture kernel?
I think using cmdline option is the simplest way. You just have to
add "noextnmi" to KDUMP_COMMANDLINE_APPEND in /etc/sysconfig/kdump.

Regards,

Hidehiro Kawai
Hitachi, Ltd. Research & Development Group