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Date: Fri, 24 Feb 2017 10:15:37 +0100
From: Ingo Molnar <mingo@kernel.org>
To: hpa@zytor.com
Cc: Peter Zijlstra <peterz@infradead.org>,
        Arjan van de Ven <arjan@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
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        richard.weinberger@gmail.com,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] x86: Implement __WARN using UD0
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* hpa@zytor.com <hpa@zytor.com> wrote:

> Incidentally, as an alternative to a #UD, int $9 could be an alternative 
> (exception vector 9 was discontinued with the 486.)

With thousands of call sites a one byte opcode would be preferred, that's why INT3 
is so nice.

Thanks,

	Ingo