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Date: Tue, 19 Jun 2012 10:52:52 +0200
From: Wolfgang Grandegger <wg@grandegger.com>
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Subject: Re: [Xenomai] Sharing memory between rt-posix and standard-posix
 apps
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: Xenomai@xenomai.org

On 06/19/2012 10:50 AM, Gilles Chanteperdrix wrote:
> On 06/19/2012 10:49 AM, Wolfgang Grandegger wrote:
>> On 06/19/2012 10:33 AM, Gilles Chanteperdrix wrote:
>>> On 06/19/2012 10:25 AM, Wolfgang Grandegger wrote:
>>>> Hello,
>>>>
>>>> the shared memory support of Xenomai's POSIX skin currently only support
>>>> shared memory between rt processes.
>>>
>>> These services are for sharing memory between user-space and
>>> kernel-space. In order to share memory between user-space processes, you
>>> can use plain linux shared memories.
>>
>> But then I will get mode switches due to page faults, right?
> 
> No, there should not be any page fault.

But that's what we observe on a i.MX53 and i.MX6Q board. IIRC, the first
access usually results in a page fault.

Wolfgang.