Re: [PATCH] x86/alternatives: Fix optimize_nops() checking

From: David Woodhouse
Date: Wed Jan 10 2018 - 15:36:56 EST


On Wed, 2018-01-10 at 21:33 +0100, Peter Zijlstra wrote:
> On Wed, Jan 10, 2018 at 12:26:25PM -0800, Linus Torvalds wrote:
> > Imagine just how crazy that would be to debug. You'd be basically
> > executing insane code, and looking at the sources - or even the
> > binaries - it would _look_ completely sane.
>
> Been there done that.. we have too much self modifying code for that
> not to have been needed.
>
> Use gdb on /proc/kcore and disassemble self to see the _real_ code.

Or qemu -d in_asm to see what the code *was* at the time the CPU hit
it... :)

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