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Date:   Tue, 7 May 2019 17:24:18 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [RFC][PATCH 1/2] x86: Allow breakpoints to emulate call
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On Tue, 7 May 2019 12:21:59 -0500
Josh Poimboeuf <jpoimboe@redhat.com> wrote:

> regs->sp is *undefined* on x86-32.  We're damning our future selves to
> have to always remember to use that darn kernel_stack_pointer() helper
> for eternity just because of x86-32.

And there's been several times I forget that regs->sp can not be read
directly. Especially most of my bug reports are for x86_64 these days.
But when I had that seldom x86_32 one, and go debugging, I would print
out "regs->sp" and then the system would crash. And I spend some time
wondering why?

It's been a bane of mine for some time.


-- Steve