From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4C87418D.1090601@domain.hid> Date: Wed, 08 Sep 2010 09:55:57 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <4C8605E6.4000400@domain.hid> <4C862A3B.2050300@domain.hid> <4C8713A2.9010705@domain.hid> In-Reply-To: <4C8713A2.9010705@domain.hid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] How do I force a core dump on a page fault event? List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bob Feretich Cc: xenomai@xenomai.org Bob Feretich wrote: > Comments inline... > > On 9/7/2010 5:04 AM, Gilles Chanteperdrix wrote: >> Bob Feretich wrote: >>> I am seeing various Oops reports referencing my rt user task, but they >>> don't provide any useful information regarding my program's state at the >>> time of the Oops. >>> >>> The most common Oops is... >>> Unable to handle kernel NULL pointer dereference at virtual address 0000000c >>> ... snipped... >> This tells us that a bug happens in kernel-space for some reason, while >> trying to handle a user-space fault. >> >> Do you have a simple piece of code which I can run to reproduce this issue? >> > No. This problem started occurring when I integrated the whole system > together. I'm going to have to work on it a bit to reduce it to a > suitable code segment . > The Xenomai content of the loop is: > while (!end) { > ... > rc = rt_event_wait(&event1,..); > ... > rc = rt_event_clear(&event1,..); > ... > rc = rt_event_wait(&event2,..); > ... > rc = rt_event_clear(&event2,..); > ... > rc = rt_event_wait(&event3, TM_NONBLOC, ...); > if (rc==0) end = 1; > } Is this is a loop using all the CPU (all the events with TM_NONBLOCK) ? -- Gilles.