El Mon, Mar 19, 2018 at 09:28:03PM -0500 Josh Poimboeuf ha dit:
> On Mon, Mar 19, 2018 at 04:22:55PM -0700, Matthias Kaehlcke wrote:
> > > Here's a (surprisingly easy) fix for this particular issue, though I'd
> > > be shocked if there weren't a bunch more issues lurking elsewhere. Let
> > > me know how it goes.
> >
> > Thanks for having a look, this fixes the vast majority of warnings in
> > a defconfig build!
>
> Wow. Consider me shocked :-)
>
> > The remaining warnings are:
> >
> > arch/x86/mm/pti.o: warning: objtool: pti_init() falls through to next
> > function pti_user_pagetable_walk_pmd()
> > s/debugfs/file.o: warning: objtool: full_proxy_llseek() falls through to
> > next function full_proxy_read()
> > fs/debugfs/file.o: warning: objtool: full_proxy_read() falls through to
> > next function full_proxy_write()
> > fs/debugfs/file.o: warning: objtool: full_proxy_write() falls through to
> > next function full_proxy_poll()
> > fs/debugfs/file.o: warning: objtool: full_proxy_poll() falls through to
> > next function full_proxy_unlocked_ioctl()
> > fs/debugfs/file.o: warning: objtool: full_proxy_unlocked_ioctl() falls
> > through to next function fops_u8_open()
>
> These all seem to be related to some weirdness with the UD2 instruction,
> not necessarily an objtool issue per se.
>
> Any chance this fixes some of the warnings? If not, I can try to build
> with clang and look a little deeper.
>
> diff --git a/include/linux/compiler.h b/include/linux/compiler.h
> index ab4711c63601..315a8757b565 100644
> --- a/include/linux/compiler.h
> +++ b/include/linux/compiler.h
> @@ -124,7 +124,12 @@ void ftrace_likely_update(struct ftrace_likely_data *f,
> int val,
> # define ASM_UNREACHABLE
> #endif
> #ifndef unreachable
> -# define unreachable() do { annotate_reachable(); do { } while (1); } while
> (0)
> +#define unreachable() \
> + do { \
> + annotate_unreachable(); \
> + barrier_before_unreachable(); \
> + __builtin_unreachable(); \
> + } while (0)
> #endif
Thanks, unfortunately negative on this one, all the warnings are still
generated.
