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Date:   Thu, 2 May 2019 16:48:19 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     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 Thu, 2 May 2019 11:02:40 -0700
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> Indeed, the 32-bit case for same-RPL exceptions/iret is entirely
> different, and I'd forgotten about that.
> 
> And honestly, this makes the 32-bit case much worse. Now the entry
> stack modifications of int3 suddenly affect not just the entry, but
> every exit too.
> 
> This is _exactly_ the kind of subtle kernel entry/exit code I wanted
> us to avoid.

I just want to point out that I never got the trampoline version
working on i386. I didn't have the time to debug why it would crash
when stressed.

-- Steve