From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Wed, 31 Mar 2010 18:53:30 +0200
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-core] FYI: CONFIG_PERF_EVENTS conflicts with Xenomai
	shadows
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Jan Kiszka wrote:
> Hi,
> 
> just ran into an ugly warning of I-pipe as I happened to have
> CONFIG_PERF_EVENTS enabled in 2.6.32 kernel. That pulls some plain Linux
> spinlock into the finish_task_switch path.
> 
> We should either disable this feature at I-pipe level or patch it
> properly. Haven't checked yet if the latter is feasible with moderate
> effort, though.
> 

At least this one is now explainable: There is no problem related to
CONFIG_PERF_EVENTS. finish_task_switch is not part of the critical
shadow task switch, and the oops I saw finally turned out to be caused
by my buggy virtual hardware (IOW: an unrelated hypervisor bug). Nothing
to worry about for Xenomai or I-pipe.

Jan

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux