[PATCH 0/7] CFI for ARM32 using LLVM

[Sami Tolvanen]

On Tue, Feb 27, 2024 at 1:48 PM Linus Walleij <linus.walleij at linaro.org> wrote:
>
> On Tue, Feb 27, 2024 at 2:06 AM Kees Cook <keescook at chromium.org> wrote:
>
> > I wasn't able to build with CONFIG_FTRACE=y; I got this link error:
> > ld.lld: error: undefined symbol: ftrace_stub_graph
> > (FWIW, I'm building against v6.8-rc2, maybe I need a different base?)
>
> I get that too, from the buildbots, but I'm clueless about what it is.
> All of it is in generic code, nothing ARM32-specific, maybe some bug
> in v6.8-rc1 that was fixed (I wish...) Sami?

You need to just define a separate stub for graph tracing with KCFI to
avoid type mismatches. Something like this:

https://lore.kernel.org/all/20230710183544.999540-11-samitolvanen@google.com/

Sami