Re: [RFC][PATCH v3] ftrace/x86_64: Emulate call function while updating in breakpoint handler

From: Linus Torvalds
Date: Wed May 01 2019 - 15:06:15 EST


On Wed, May 1, 2019 at 11:52 AM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>
> I got Peter's patch working. Here it is. What do you think?

I can tell from just looking at it for five seconds that at least the
32-bit case is buggy.

You can't look at CS(%rsp) without first also checking that you're not
coming from vm86 mode.

But other than that I guess it does end up being pretty simple.

Linus