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Date: Thu, 01 Jan 2004 23:24:03 +0800
From: David Xu <davidxu@freebsd.org>
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To: Doug Rabson <dfr@nlsystems.com>
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cc: arch@freebsd.org
Subject: Re: sigaltstack with threads
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Doug Rabson wrote:
> I think that if its supported at all in threaded programs, it must be
> per-thread state otherwise you can't prevent two different threads
> colliding on the same signal stack. I can't quite see how this maps to
> KSE/KSEG since I only have the most hazy model of that stuff in my head
> right now.
> 
> Anyway, I've worked around things by not setting SA_ONSTACK for the
> handlers that I want to run on the thread stack.
> 
> 
I have worked out a patch to support per-thread sigaltstack() state,
in most cases, it is just a literally replacement.

http://people.freebsd.org/~davidxu/kse/kern_sigaltstack.diffs

David Xu