Re: [PATCH 2/4] x86/kprobes: Fix frame pointer annotations

From: Peter Zijlstra
Date: Wed May 08 2019 - 11:40:27 EST


On Wed, May 08, 2019 at 07:42:48AM -0500, Josh Poimboeuf wrote:
> On Wed, May 08, 2019 at 02:04:16PM +0200, Peter Zijlstra wrote:

> > Do the x86_64 variants also want some ORC annotation?
>
> Maybe so. Though it looks like regs->ip isn't saved. The saved
> registers might need to be tweaked. I'll need to look into it.

What all these sites do (and maybe we should look at unifying them
somehow) is turn a CALL frame (aka RET-IP) into an exception frame (aka
pt_regs).

So regs->ip will be the return address (which is fixed up to be the CALL
address in the handler).