From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Mon, 05 Nov 2007 20:16:39 +0100
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: [Xenomai-core] [PATCH] i386: switch to root domain on unhandled
	non-root faults
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This patch addresses the recently discovered issue that I-pipe actually
need to deal with faults over non-root domain in which the current
domain shows no interest in. Such faults could be triggered inside
copy_*_user, thus can cleanly be handled by Linux - if we only allow for
this. Currently, if debugging is on, we warn about a potential bug, and
corrupt the pipeline states otherwise.

The new approach is to unconditionally drop to root domain in such
cases, but - for debugging purposes of non-fixable faults - keep track
of the original domain and report it on oops.

Similar patches are required for other archs. Maybe I can look into
x86_64 later.

Jan

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