linux-kernel - Re: [PATCH 1/2] coredump: flush the fpu exit state for proper multi-threaded core dump

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Message-ID: <CA+55aFwsZu6YhfeKp17TuiZuyxEXgReXVUMh+_drM7410SBiyg@mail.gmail.com>
Date:	Mon, 7 May 2012 12:15:35 -0700
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	Suresh Siddha <suresh.b.siddha@...el.com>
Cc:	hpa@...or.com, mingo@...e.hu, oleg@...hat.com,
	suresh@...stanetworks.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] coredump: flush the fpu exit state for proper
 multi-threaded core dump

On Mon, May 7, 2012 at 12:07 PM, Suresh Siddha
<suresh.b.siddha@...el.com> wrote:
>
> Fix this by explicitly flushing the fpu state in do_exit() by calling
> prepare_to_copy()

Ugh, I hate this one.

We're making the exit path more expensive for almost no gain. The FPU
state is dead in 99.9% of all cases.

Why isn't this a core-dump-only case?

                    Linus
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