From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Thu, 28 Oct 2010 21:37:27 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-core] arm: Unprotected access to irq_desc field?
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: Xenomai core <Xenomai-core@domain.hid>

Jan Kiszka wrote:
> Gilles,
> 
> I happened to come across rthal_mark_irq_disabled/enabled on arm. On
> first glance, it looks like these helpers manipulate irq_desc::status
> non-atomically, i.e. without holding irq_desc::lock. Isn't this fragile?

>>From my point of view, locking anything would be overkill on ARM: irq
configurations are completely static as per the board, and so, ARMs can
use proper irq demuxing, instead of the "shared irqs" workaround. So, in
other word, I do not see why we would need any locking.


-- 
                                                                Gilles.