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Date: Wed, 26 Nov 2003 11:04:47 -0800
From: Bruce Perens <bruce@perens.com>
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To: Linus Torvalds <torvalds@osdl.org>
Cc: Ulrich Drepper <drepper@redhat.com>,
       Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Never mind. Re: Signal left blocked after signal handler.
References: <20031126173953.GA3534@perens.com> <Pine.LNX.4.58.0311260945030.1524@home.osdl.org> <3FC4ED5F.4090901@perens.com> <3FC4EF24.9040307@perens.com> <3FC4F248.8060307@perens.com> <Pine.LNX.4.58.0311261037370.1524@home.osdl.org>
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What happened is that I attempted to simplify the test code to send to 
you, and simplified out the problem by using
kill() instead of causing a fault. :-)

It's just what you describe here:

>One difference in 2.4.x and 2.6.x is the signal blocking wrt blocked
>signals that are _forced_ (ie anything that is thread-synchronous, like a
>SIGSEGV/SIGTRAP/SIGBUS that happens as a result of a fault):
>
> - in 2.4.x they will just punch through the block
> - in 2.6.x they will refuse to punch through a blocked signal, but
>   since they can't be delivered they will cause the process to be
>   killed
>  
>
The behavior of 2.4 seems to be the same used by some dozens of Unix 
systems upon which my confidence test passed.

I agree that we should not be wrong in the same way as everyone else, 
and wonder if POSIX says anything about this. I could have been the only 
one using this "feature".

    Thanks

    Bruce