From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <51AF1561.6090401@xenomai.org>
Date: Wed, 05 Jun 2013 12:39:29 +0200
From: Philippe Gerum <rpm@xenomai.org>
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Subject: [Xenomai] [POWERPC] bug alert with CONFIG_XENO_HW_UNLOCKED_SWITCH,
 >= kernel 3.4
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To: "Xenomai@xenomai.org" <Xenomai@xenomai.org>


A bad bug has been fixed in the unlocked context switching code for 
powerpc platforms. This affects all I-pipe patches for 3.4 kernels and 
above. The typical manifestation of this bug is random segmentation 
faults in user-space applications (sometimes after hours under stress 
load), usually the Xenomai-dependent ones.

A work around not to change the kernel code is to disable 
CONFIG_XENO_HW_UNLOCKED_SWITCH. Patches for fixing this issue are 
available for 3.5.7 and above:

http://git.xenomai.org/?p=ipipe.git;a=commit;h=614aa59453dacf7693fbb18229c27676c2803dbb
http://git.xenomai.org/?p=ipipe.git;a=commit;h=04ea520ab96a16ec65529a2efed92c9a4a8bda34

You might need this companion patch too: 
http://git.xenomai.org/?p=ipipe.git;a=commit;h=047a21b3b203a1fbfce21284f01e376a2cf54c19

HTH,

-- 
Philippe.