From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 23 Dec 2011 12:33:09 -0500 Message-ID: <20111223173309.GM27742@domain.hid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline From: lsorense@domain.hid (Lennart Sorensen) Subject: [Xenomai-core] CONFIG_XENO_HW_UNLOCKED_SWITCH=y causes random process corruption in xenomai 2.6.0 on powerpc. List-Id: Xenomai life and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: xenomai@xenomai.org After spending quite a while trying to explain how things like /bin/echo could possibly segfault, I finally discovered that the new feature in xenomai 2.6.0 (new when moving from 2.4.10 that is) of having preemptible context switches is what is corrupting the state of random linux processes once in a while. After turning the option off, I haven't seen a single crash just like 2.4.10. So something subtle is wrong with this option. It appears to be most likely to occour (possibly only likely) when xenomai is handling interrupts. It seems that getting an interrupt in the middle of a context switch at the wrong time corrupts the process that is being switched to or from (no idea which it is). Unless someone can think of a way to track down and fix this I would certainly suggest making the option off by default instead of on. With CONFIG_XENO_HW_UNLOCKED_SWITCH=n I don't have any problems anymore. -- Len Sorensen