[tip:x86/debug] x86/kdump: No need to disable ioapic/ lapic in crash path

[Don Zickus]

On Fri, Feb 17, 2012 at 04:41:01AM -0800, Eric W. Biederman wrote:
> 
> The fix with a guarantee of no more scope creep is to just disable the
> nmi watchdog on the kexec on panic path.
> 
> Don if you have time please figure out is needed to ignore nmi's and
> possible record and/or report them while we boot, otherwise please cook
> up a patch that just disables the nmi watchdog wherever we are sending
> it from (the local apic or the ioapic).

Can I keep things even simpler?  The original problem was the deadlock
with the ioapic lock.  We fixed that by removing the call to
disable_IO_APIC().  Can we just leave the disable_local_APIC calls in
there for now?  Is there any real harm?

All this rewrite is going to take time which will delay fixing a current
problem with kexec on panic, the ioapic deadlock.

Thoughts?

Cheers,
Don