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Date: Sun, 3 Nov 2002 16:53:39 -0800
From: William Lee Irwin III <wli@holomorphy.com>
To: Pete Zaitcev <zaitcev@redhat.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: interrupt checks for spinlocks
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From: William Lee Irwin III <wli@holomorphy.com>
>>>> (1) check that spinlocks are not taken in interrupt context without
>>>> 	interrupts disabled

At some point in the past, Pete Zaitcev wrote:
>>> Bill, why is this bad? I routinely use this technique.

From: William Lee Irwin III <wli@holomorphy.com>
>> If you receive the same interrupt on the same cpu and re-enter code
>> that does that, you will deadlock.

On Sun, Nov 03, 2002 at 07:42:49PM -0500, Pete Zaitcev wrote:
> How would that happen? I thought it was not possible to re-enter
> an interrupt, and that it was pretty fundamental for Linux.
> When did we allow it, and what are implications for architectures?

This non-reentrant stuff hurts my head. Another patch down the
toilet, I guess.


Bill
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