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Date: Fri, 30 Jan 2015 09:25:14 +0000 (GMT)
From: "Maciej W. Rozycki" <macro@linux-mips.org>
To: Aaro Koskinen <aaro.koskinen@iki.fi>
cc: Ralf Baechle <ralf@linux-mips.org>, David Daney <david.daney@cavium.com>,
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        Hemmo Nieminen <hemmo.nieminen@iki.fi>, stable@vger.kernel.org
Subject: Re: [PATCH v2 2/2] MIPS: fix kernel lockup or crash after CPU
 offline/online
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On Thu, 15 Jan 2015, Aaro Koskinen wrote:

> As printk() invocation can cause e.g. a TLB miss, printk() cannot be
> called before the exception handlers have been properly initialized.
> This can happen e.g. when netconsole has been loaded as a kernel module
> and the TLB table has been cleared when a CPU was offline.

 Hmm, why can a call to `printk' cause a TLB miss, what's so special about 
this function?  Does it use kernel mapped addresses for any purpose such 
as `vmalloc'?

  Maciej