From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Mon, 09 Mar 2009 18:27:17 +0100
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-core] Watchdog / immediate Linux signal delivery
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Philippe Gerum wrote:
> Jan Kiszka wrote:
>> Meanwhile I played with some light-weight approach to relax a thread
>> that received a signal (according to do_sigwake_event). Worked, but only
>> once due to a limitation (if not bug) of I-pipe x86: in __ipipe_run_isr,
>> it does not handle the case that a non-root handler may alter the
>> current domain, causing corruptions to the IPIPE_SYNC_FLAG states of the
>> involved domains.
> 
> It is not a bug, this is wanted. ISR must neither change the current
> domain nor migrate CPU; allowing this would open Pandora's box.

And if there is no way to migrate from within an ISR, we can bury any
attempt to deliver signals to spinning Xenomai threads - or what other
context would remain to Xenomai for triggering migration?

Jan

-- 
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux