From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Weber <jweber@domain.hid>
Date: Mon, 16 Apr 2007 16:27:01 -0500
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Subject: Re: [Xenomai-help] page faults
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: Xenomai Help <xenomai@xenomai.org>

On Monday 16 April 2007 15:43, Gilles Chanteperdrix wrote:
> If the fault you observe is due to an access to some memory after a call
> to fork or one of its derivative (such as system, popen, etc...), the
> patch would have copied the whole real-time process address space at
> fork time instead of setting up COW mappings.
No process forks are involved.  Though mlockall() was called from Linux 
main(), and the page fault was encountered by a separate Xenomai task.  
Here's the task history:

static constructor allocates buffer from heap
enter main()
call mlockall(), verify return status == 0
buffer is forcibly cleared using memset(buffer, 0, sizeof(buffer))
main calls rt_task_shadow() to create Xenomai startup task
startup task spawns Xenomai communications task via rt_task_start()
communications task encounters page fault

Let me know if you are able to spot the source of the page faults.

	thanks,
	Jeff