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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 19 Apr 2012 11:11:00 -0700
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Subject: Re: [PATCH 3/3] x86, extable: Handle early exceptions
To: Borislav Petkov <bp@amd64.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>
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On Thu, Apr 19, 2012 at 10:38 AM, Borislav Petkov <bp@amd64.org> wrote:
>
> OTOH, if we can share early and normal exception handling lookup code, then a
> perfect hash would make sense as those exceptions would pile up.

Oh, any of this only makes sense if we can share it with the runtime
exception lookup.

They are *seldom* hugely performance-critical, but there are some
unusual loads where you do get a fair number of exceptions.

               Linus