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Subject: Re: [rfc] [patch] kernel hooks
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       "Michael Grundy" <vamsi_krishna@in.ibm.com>,
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From: "Richard J Moore" <richardj_moore@uk.ibm.com>
Date: Thu, 3 Oct 2002 14:32:50 +0100
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> You must also ensure that the code you are modifying isnt on an IRQ path
> (if it is you must do spin locks and then be very careful about cross
> cpu tlb deadlocks). Finally you have no choice but to ensure you never
> use it on the NMI path

Why do we need a spinlock? We change one byte, we are not concered about
when exactly that takes effect, only that there are always valid
instructions in the pipeline.

Richard.

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