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Date: Mon, 02 Apr 2012 15:01:26 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Masami Hiramatsu <masami.hiramatsu@gmail.com>
CC: linux-kernel@vger.kernel.org, Huang Ying <ying.huang@intel.com>,
        Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Ingo Molnar <mingo@redhat.com>,
        Jason Wessel <jason.wessel@windriver.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [RFC PATCH -tip 00/16] in-kernel x86 disassember
References: <20120401160229.4502.2541.stgit@shimauta>
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On 04/01/2012 09:02 AM, Masami Hiramatsu wrote:
> Hi,
> 
> Here is a series of patches of the in-kernel x86 disassembler
> for the latest tip tree.
> This will show you a pretty disassembled code instead of
> just a digital code sequence when you gets a kernel panic etc.
> (I know, we also have script/decodecode for the panic use)
> 
> This feature is not for users, but mainly for kernel developers
> who can understand disassembly code of x86 ;). This is just like
> a joke feature in kernel. (yeah, I spend my spare time for this.
> It's my fun :))
> 

This is cool, but I have one major reservation about it: it will make
kernel panics take a lot more screen real estate without containing more
information, and we already have problems with things scrolling off way
too easily.

For that reason I would like to request that this *only* enabled by an
explicit command-line option or similar (disasm_oops, maybe?), so that
the user has to opt-in.  In other words, if *you* are debugging your own
kernel, and don't expect to ship oopses off to someone else.

	-hpa