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Subject: Re: 85xx Address space query
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: kernel mailz <kernelmailz@googlemail.com>
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Date: Thu, 25 Jun 2009 21:33:01 +1000
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On Wed, 2009-06-24 at 23:16 +0530, kernel mailz wrote:
> But If the app was running with PID=1, interrupt occurs, kernel code
> gets executed in PID=1, how does the kernel handle this ? and goes
> back to PID=0, since its translations are all in PID=0

PID 0 is a special case in HW. TLB entries with TID=0 will match any PID
value.

Cheers,
Ben.