Re: [PATCH v13 13/14] unwind_user/x86: Enable frame pointer unwinding on x86
From: Steven Rostedt
Date: Fri Jul 11 2025 - 12:13:51 EST
On Fri, 11 Jul 2025 09:43:21 +0100
David Laight <david.laight.linux@xxxxxxxxx> wrote:
> On Mon, 07 Jul 2025 21:22:52 -0400
> Steven Rostedt <rostedt@xxxxxxxxxx> wrote:
>
> > From: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> >
> > Use ARCH_INIT_USER_FP_FRAME to describe how frame pointers are unwound
> > on x86, and enable CONFIG_HAVE_UNWIND_USER_FP accordingly so the
> > unwind_user interfaces can be used.
>
> How is that going to work?
> Pretty much all x86 userspace is compiled with bp as a general
> purpose register not a frame pointer.
Which is where this patch set comes in...
https://lore.kernel.org/linux-trace-kernel/20250701184939.026626626@xxxxxxxxxxx
-- Steve