Re: linux-next: Tree for July 18: warning at kernel/lockdep.c:2068 trace_hardirqs_on_caller

Dave Hansen
2008-07-20T09:01:21Z

On Sun, 2008-07-20 at 01:11 +0200, Vegard Nossum wrote:
> Maybe the firmware memmap code can simply run a little later in the
> boot sequence?

Heh, I'm catching up on this thread...

It is possible that it could run later. But, I do know that there are
at least a couple of these tables (on various arches) that we toss out
of memory or become unavailable later in boot.

I do this this:

sysfs: add /sys/firmware/memmap

is really being done at the wrong level. I don't, for instance, see
*any* reference to memory hotplug in these patches. That's because
they're done against firmware structures, and memory hotplug doesn't
update firmware structures on the two architectures that I can remember
(ppc64 and x86).

In other words, kexec using this probably won't work on a memory hotplug
machine.

Secondly, why don't we just modify the
existing /sys/devices/system/memory things to properly export what exec
needs? They're already cross-platform *and* they're updated with memory
hotplug events.

-- Dave