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Date: Fri, 16 Jun 2006 09:09:22 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
cc: LKML <linux-kernel@vger.kernel.org>, ashok.raj@intel.com
Subject: Re: [RFC][PATCH] avoid cpu hot remove of cpus which have special RT
 tasks.
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On Fri, 16 Jun 2006, KAMEZAWA Hiroyuki wrote:

> When cpu hot remove happens, tasks on the target cpu will be migrated even if
> no available cpus in tsk->cpus_allowed. (See: move_task_off_dead_cpu().)

Could we kill the process instead? If a process has been forced to run on 
a certain cpu then it is an error to migrate it to a different one. If a 
system wiil do cpu hot remove then the system needs to be configured in 
such a way as to allow processes to be migrated to other processors.