Re: [GIT PULL] x86/boot changes for v3.13

[Ingo Molnar <mingo@kernel.org>]

* Borislav Petkov <bp@alien8.de> wrote:

> On Tue, Nov 12, 2013 at 12:23:38PM +0100, Ingo Molnar wrote:
> > So I suspect what Yinghai tried to say if CPU0 and CPU1 are not on the
> > same node we do the printout incorrectly.
> 
> I hope your translation is correct :) I'd still like to get a
> confirmation from him though.
> 
> > Arguably this was a pre-existing condition, but would be nice to fix
> > it now that this code has emerged out of steady bitrot! :-)
> >
> > How difficult would it be in your opinion?
> 
> Well, I did try a weird, non-existant configuration:
> 
> kvm ... -smp 6 -numa node,nodeid=0,cpus=0\;2\;3 -numa node,nodeid=1,cpus=1\;4\;5
> 
> and what I get is:
> 
> [    0.068574] x86: Booting SMP configuration:
> [    0.069006] .... node  #1, CPUs:      #1
> [    0.147005] .... node  #0, CPUs:   #2 #3 #4 #5
> [    0.445273] x86: Booted up 2 nodes, 6 CPUs
> 
> Before my cleanup and after removing the "fixing up alternatives"
> message which hid things, the output looked like:
> 
> [    0.069621] smpboot: Booting Node   1, Processors  #   1 OK
> [    0.146006] smpboot: Booting Node   0, Processors  #   2 #   3 #   4 #   5 OK
> [    0.448320] Brought up 6 CPUs
> 
> The problem is not the indentation but that the current code slaps all 
> cpus on the last node, in this case node 0, because announce_cpu gets 
> the cores one by one.
> 
> A possible fix would be to collect the topology and dump it *only* 
> *after* the last core has been announced.

Hm, I think it's actually a bonus that we see the individual CPUs printed 
as they boot up. That way if there's a hang, the place where it hangs is 
apparent, etc.

Thanks,

	Ingo