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Date: Tue, 23 May 2006 17:51:13 -0500
From: Nathan Lynch <ntl@pobox.com>
To: Giuliano Pochini <pochini@shiny.it>
Subject: Re: CPU 1 refused to die!
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Giuliano Pochini wrote:
> 
> I booted with maxcpus=1, then I enabled the 2nd cpu
> with echo 1 > /sys/devices/system/cpu/cpu1/online

So onlining at runtime seems to work.  Did you verify that tasks get
run on the 2nd cpu after you online it?  Any other strange messages in
dmesg?

> I can't disable it anymore. dmesg says "CPU 1 refused to die!".

But offlining doesn't.

Can you online and offline cpus if you boot without maxcpus=1?