From mboxrd@z Thu Jan  1 00:00:00 1970
From: Philippe Gerum <rpm@xenomai.org>
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References: <4CC998FB.3070102@domain.hid>  <4CC9CBE1.6030006@domain.hid>
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Date: Thu, 28 Oct 2010 21:34:29 +0200
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Subject: Re: [Xenomai-core] arm: Unprotected access to irq_desc field?
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: Jan Kiszka <jan.kiszka@domain.hid>, Xenomai core <Xenomai-core@domain.hid>

On Thu, 2010-10-28 at 21:15 +0200, Gilles Chanteperdrix wrote:
> 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?
> 
> I have no idea. How do the other architectures do? As far as I know,
> this code has been copied from there.

Other archs do the same, simply because once an irq is managed by the
hal, it may not be shared in any way with the regular kernel. So locking
is pointless.

-- 
Philippe.