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Date: Thu, 26 Feb 2009 21:18:32 +0100
Message-ID: <19f34abd0902261218u388de998l1204857bde9bbe32@mail.gmail.com>
Subject: Re: [RFC][PATCH] signals: don't copy siginfo_t on dequeue
From: Vegard Nossum <vegard.nossum@gmail.com>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>, Pekka Enberg <penberg@cs.helsinki.fi>,
       linux-kernel@vger.kernel.org
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2009/2/26 Oleg Nesterov <oleg@redhat.com>:
> So. dequeue_signal() returns NULL if there is no siginfo queued. In that
> case we assume that the signal is not pending.
>
> But this is not right. Think about SEND_SIG_FORCED, or __sigqueue_alloc()
> failure when the signal is sent. Or look at zap_other_threads() for example,
> it just sets the bit in ->pending but doesn't queue siginfo.

I will investigate. Thanks for looking, and thanks for the pointers :-)


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036