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Subject: Re: [PATCH] arm: Add unwinding annotations for 64bit division
 functions
From: "Jon Medhurst (Tixy)" <jon.medhurst@linaro.org>
To: Russell King - ARM Linux <linux@arm.linux.org.uk>
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Date: Thu, 22 Sep 2011 08:28:08 +0100
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On Wed, 2011-09-21 at 12:55 +0100, Russell King - ARM Linux wrote:
> Instructions such as VFP, kprobes tracing, etc are expected fault
> locations, and those are fairly well controlled where they can be placed.
> With things like ftrace, it certainly is the case that the unwinder can
> theoretically be called from almost anywhere in a function.

Actually, kprobes can be places on any instruction in the kernel that
isn't in the section .kprobes.text.

I also strongly suspect that stack unwinding won't happen correctly
across the boundary between the kprobes handling code and the function
which was probed - there's an awful lot of stack jiggery pokery going on
there.

-- 
Tixy