From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4EB6ECA8.8080806@domain.hid> Date: Sun, 06 Nov 2011 14:23:04 -0600 From: at91_enthus MIME-Version: 1.0 References: <4EB6CA3B.1040608@domain.hid> <4EB6CB8A.2020303@domain.hid> <4EB6CDB0.6070306@domain.hid> <4EB6D11A.6070008@domain.hid> <4EB6D2A4.2020102@domain.hid> <4EB6D941.7080206@domain.hid> <4EB6DA0E.9070802@domain.hid> <4EB6E5FB.3010809@domain.hid> <4EB6E7E5.3070303@domain.hid> In-Reply-To: <4EB6E7E5.3070303@domain.hid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] Xenomai 2.6.0 - kernel seg faults on AT91 List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: xenomai@xenomai.org On 11/06/2011 02:02 PM, Gilles Chanteperdrix wrote: > On 11/06/2011 08:54 PM, at91_enthus wrote: >> On 11/06/2011 01:03 PM, Gilles Chanteperdrix wrote: >>> On 11/06/2011 08:00 PM, at91_enthus wrote: >>>> On 11/06/2011 12:32 PM, Gilles Chanteperdrix wrote: >>>>> On 11/06/2011 07:25 PM, at91_enthus wrote: >>>>>> On 11/06/2011 12:10 PM, at91_enthus wrote: >>>>>>> On 11/06/2011 12:01 PM, Gilles Chanteperdrix wrote: >>>>>>>> On 11/06/2011 06:56 PM, at91_enthus wrote: >>>>>>>>> Hi. >>>>>>>>> >>>>>>>>> I gave Xenomai 2.6.0 a try and installed a newly patched kernel on my >>>>>>>>> AT91SAM9G20 board. >>>>>>>>> >>>>>>>>> Here is my setup: >>>>>>>>> >>>>>>>>> proc: AT91SAM9G20 >>>>>>>>> kernel: 2.6.35.9 >>>>>>>>> OS: embedded Debian Squeeze >>>>>>>>> >>>>>>>>> The board boots fine up to stage 2 (user terminal). Sometimes, I am able >>>>>>>>> to get a login terminal, despite seg fault messages. >>>>>>>>> >>>>>>>>> A similar behavior occurs in a Xenomai capable 2.6.37 kernel, only >>>>>>>>> without the fault messages. In this case the board simply freezes. >>>>>>>>> >>>>>>>>> I included the files (.config and fault messages) in the attachments. >>>>>>>>> >>>>>>>> You enabled CONFIG_FCSE_GUARANTEED, I do not think Debian squeeze can >>>>>>>> boot with that, you need a real embedded filesystem, or use >>>>>>>> CONFIG_FCSE_BEST_EFFORT. >>>>>>>> >>>>>>>> >>>>>>> Since I've started looking in to Xenomai, I have been using FCSE >>>>>>> "guaranteed" and "best efort" along with both Debian Squeeze and Lenny >>>>>>> (Xenomai 2.5 series) without any issues. >>>>>>> >>>>>>> I'll change the FCSE setting to see if I get a different behavior. >>>>>>> >>>>>>> Regards. >>>>>> I put the results for CONFIG_FCSE_BEST_EFFORT in the attachment. >>>>> Unusable. To make it usable, the following options are lacking: >>>>> CONFIG_FCSE_MESSAGES >>>>> CONFIG_FRAME_POINTER >>>> I couldn't find this option. >>> You need to disable STACK_UNWIND. Without it, some stack traces are >>> unreadable such as the one you keep sending. >>> >> rc.local looked suspicious in the debug messages. >> >> To be more exact, it contained the following lines: >> >> #! /bin/sh >> chmod 777 /proc/xenomai/latency >> echo "1000" > /proc/xenomai/latency >> exit 0 >> >> The setting came from the previous installation, because I kept getting >> negative values for latencies. > Note that you can hardwire a value for the latency in the kernel > configuration. > >> Anyway, I removed the offending lines and my system boots correctly. If >> I enter the lines by hand, I get no segfaults. However, if I try to >> execute /etc/rc.local (with the two lines uncommented) by hand, the >> kernel seg faults and the system freezes. >> >> Odd. > Yes, really odd. I am unable to reproduce this issue. > > What was the last version known to be working? > I think I found the main culprit, although I can't figure out the mechanism. In an earlier post, I stated that the contents in rc.local crashed the system and if I entered the lines manually nothing happened. BASH is used at console level, sh in rc.local. If I set "sh" in the console and execute the two lines manually, the system locks. Therefore, for some strange reason, sh is detrimental to xenomai. The question is why this happens in 2.6 and not 2.5.*.