From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 1/1] x86: fix text_poke
Date: Fri, 25 Apr 2008 08:03:27 -0700 (PDT)
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References: <20080425.021301.193689806.davem@davemloft.net> <1209343883-7991-1-git-send-email-jirislaby@gmail.com>
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Cc: David Miller <davem@davemloft.net>, zdenek.kabelac@gmail.com,
	rjw@sisk.pl, paulmck@linux.vnet.ibm.com, akpm@linux-foundation.org,
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	"H. Peter Anvin" <hpa@zytor.com>,
	Jeremy Fitzhardinge <jeremy@goop.org>,
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To: Jiri Slaby <jirislaby@gmail.com>
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On Mon, 28 Apr 2008, Jiri Slaby wrote:
> 
> Thanks. Bisected mm down to git-x86.patch, bisected git-x86-latest down to
> x86: enhance DEBUG_RODATA support - alternatives
> The patch below fixes the problem for me. Comments welcome.

You're a hero, Jiri.

And that also explains why I didn't see it - I don't do modules.

Thanks a heap.

> The 0xf0 pattern comes from alternatives_smp_lock:
> text_poke(*ptr, ((unsigned char []){0xf0}), 1);

And we should really add a lot more sanity checking there.

		Linus