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

[Borislav Petkov]

On Fri, Oct 02, 2015 at 12:58:02AM +0000, æåèå / KAWAIïHIDEHIRO wrote:
> > On Thu, Oct 01, 2015 at 10:24:19AM +0000, æåèå / KAWAIïHIDEHIRO wrote:
> > > But how do we check if the starting kernel is a dump capture kernel?
> > 
> > How does that first kernel pass info to the capture kernel?
> 
> As I described in the previous mail,

I meant: "How does the first kernel pass info to the capture kernel by
*not* using the kernel command line"?

The kernel command line is not the channel to pass data to the kdump
kernel.

> Yes, your first kernel doesn't get external NMIs, but basically
> you don't have to set "noextnmi" option to the first kernel.

So it doesn't belong there as a kernel command line parameter in the
first place.

IOW, you need a different method to pass data to the second kernel. Be
it an ELF header, be it a shared page, whatever.

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
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