Re: [PATCH v4] ARM: imx: Fix suspend/resume crash with Clang CFI

[Sami Tolvanen]

On Fri, Aug 28, 2026 at 11:29 AM Nick Desaulniers
<ndesaulniers@xxxxxxxxxx> wrote:
>
> On Thu, Aug 27, 2026 at 12:46 PM Yo'av Moshe <linux@xxxxxxxxxxxxx> wrote:
> >
> > Note: linux/uaccess.h is included before linux/cfi.h because
> > cfi_get_func_hash() uses get_kernel_nofault() and cfi.h does not
> > include uaccess.h itself.
>
> Ah, no, we (you) should fix that. include/linux/cfi.h should IWYU.

Nathan fixed this here:

https://lore.kernel.org/lkml/20260604-tracing-fix-cfi-h-build-error-v1-1-b27015390901@xxxxxxxxxx/

> > -ENTRY(imx6_suspend)
> > +#ifdef CONFIG_CFI
> > +       /*
> > +        * Pad the location counter so that the type hash emitted by
> > +        * SYM_TYPED_FUNC_START() below ends on an 8-byte boundary:
> > +        * fncpy() requires the function entry to be 8-byte aligned.
> > +        */
> > +       .align  3
> > +       .4byte  0
>
> I still don't like these assembler directives inline like this; this
> feels like we should have perhaps a new macro in
> include/linux/cfi_types.h. Thoughts, Sami?
>
> One that garuntees the 8B alignment of the symbol for w/e that
> function patching routine requires?

Sounds like arm should override SYM_TYPED_FUNC_START to add whatever
alignment is needed?

Sami