Re: [PATCH 0/8] unwind, arm64: add sframe unwinder for kernel

Song Liu
2025-02-14T18:10:41Z

Hi Puranjay,

Thanks for running the tests.

On Fri, Feb 14, 2025 at 12:56 AM Puranjay Mohan <puranjay@kernel.org> wrote:
[...]
> >
> > I am really curious whether you have the same problem in your
> > setup.
>
> Hi Song,
>
> I did this test and found the same issue as you (gdb assembly broken),
> but I can see this issue even without the inlining. I think GDB tried to
> load the debuginfo and that is somehow broken therefore it fails to
> disassemblt properly.

Yes, this matches my observations: gcc-11 generates the .ko that
confuses gdb.

I tested with two versions of gdb (10.2 and 14.2), both have the
problem. OTOH, lldb is able to disassemble copy_process from a
gcc-compiled .ko file properly.

> But even with inlining, I couldn't see the warning about the refcount
> with my setup.

This also matches my observations. gcc-11 compiled livepatch
works fine.

Thanks,
Song