From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <4B59E2D4.5040004@domain.hid>
Date: Fri, 22 Jan 2010 18:39:32 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
MIME-Version: 1.0
References: <4B59D952.30202@domain.hid>
	<1264181859.2350.152.camel@domain.hid>
In-Reply-To: <1264181859.2350.152.camel@domain.hid>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Xenomai-core] Domain switch during page fault handling
List-Id: Xenomai life and development <xenomai.xenomai.org>
List-Unsubscribe: <https://mail.gna.org/listinfo/xenomai-core>,
	<mailto:xenomai-core-request@domain.hid>
List-Archive: </public/xenomai-core>
List-Post: <mailto:xenomai@xenomai.org>
List-Help: <mailto:xenomai-core-request@domain.hid>
List-Subscribe: <https://mail.gna.org/listinfo/xenomai-core>,
	<mailto:xenomai-core-request@domain.hid>
To: Philippe Gerum <rpm@xenomai.org>
Cc: Jan Kiszka <jan.kiszka@domain.hid>, Wolfgang Mauerer <wolfgang.mauerer@domain.hid>, xenomai-core <xenomai@xenomai.org>

Philippe Gerum wrote:
> On Fri, 2010-01-22 at 17:58 +0100, Jan Kiszka wrote: 
>> Hi guys,
>>
>> we are currently trying to catch an ugly Linux pipeline state corruption
>> on x86-64.
>>
>> Conceptual question: If a Xenomai task causes a fault, we enter
>> ipipe_trap_notify over the primary domain and leave it over the root
>> domain, right? Now, if the root domain happened to be stalled when the
>> exception happened, where should it normally be unstalled again,
>> *for_that_task*? Our problem is that we generate a code path where this
>> does not happen.
> 
> xnhadow_relax -> ipipe_reenter_root -> finish_task_switch ->
> finish_lock_switch -> unstall
> 
> Since xnshadow_relax is called on behalf the event dispatcher, we should
> expect it to return with the root domain unstalled after a domain
> downgrade, from primary to root.

Ok, but what about local_irq_restore_nosync at the end of the function ?

-- 
					    Gilles.