From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Agner Subject: Re: [PATCH 2/2] Compiler Attributes: naked can be shared Date: Mon, 17 Sep 2018 20:19:50 -0700 Message-ID: <40a059bad54389ff2a9ddc26b9d99a4b@agner.ch> References: <20180913235941.31211-1-miguel.ojeda.sandonis@gmail.com> <20180913235941.31211-3-miguel.ojeda.sandonis@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180913235941.31211-3-miguel.ojeda.sandonis@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Miguel Ojeda , arnd@arndb.de, Greg Kroah-Hartman Cc: Linus Torvalds , linux-kernel@vger.kernel.org, Rasmus Villemoes , Eli Friedman , Christopher Li , Kees Cook , Ingo Molnar , Geert Uytterhoeven , Masahiro Yamada , Joe Perches , Dominique Martinet , linux-sparse@vger.kernel.org List-Id: linux-sparse@vger.kernel.org On 13.09.2018 16:59, Miguel Ojeda wrote: > The naked attribute is supported by at least gcc >= 4.6 (for ARM, > which is the only current user), gcc >= 8 (for x86), clang >= 3.1 > and icc >= 13. See https://godbolt.org/z/350Dyc > > Therefore, move it out of compiler-gcc.h so that the definition > is shared by all compilers. > > This also fixes Clang support for ARM32 --- 815f0ddb346c > ("include/linux/compiler*.h: make compiler-*.h mutually exclusive"). > > Cc: Stefan Agner > Cc: Rasmus Villemoes > Cc: Eli Friedman > Cc: Christopher Li > Cc: Kees Cook > Cc: Ingo Molnar > Cc: Geert Uytterhoeven > Cc: Greg Kroah-Hartman > Cc: Masahiro Yamada > Cc: Joe Perches > Cc: Dominique Martinet > Cc: Linus Torvalds > Cc: linux-sparse@vger.kernel.org > Suggested-by: Arnd Bergmann > Reviewed-by: Luc Van Oostenryck > Reviewed-by: Nick Desaulniers > Signed-off-by: Miguel Ojeda Reviewed-by: Stefan Agner Ideally this two patches should go into v4.19. Not sure which path the patch should take, MAINTAINERS is not quite clear about that. This fixes 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") for ARM32, which has been merged directly by Linus, afaict... -- Stefan > --- > include/linux/compiler-gcc.h | 8 -------- > include/linux/compiler_types.h | 8 ++++++++ > 2 files changed, 8 insertions(+), 8 deletions(-) > > diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h > index 25d3dd6b2702..4d36b27214fd 100644 > --- a/include/linux/compiler-gcc.h > +++ b/include/linux/compiler-gcc.h > @@ -79,14 +79,6 @@ > #define __noretpoline __attribute__((indirect_branch("keep"))) > #endif > > -/* > - * it doesn't make sense on ARM (currently the only user of __naked) > - * to trace naked functions because then mcount is called without > - * stack and frame pointer being set up and there is no chance to > - * restore the lr register to the value before mcount was called. > - */ > -#define __naked __attribute__((naked)) notrace > - > #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) > > #define __optimize(level) __attribute__((__optimize__(level))) > diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h > index 3525c179698c..db192becfec4 100644 > --- a/include/linux/compiler_types.h > +++ b/include/linux/compiler_types.h > @@ -226,6 +226,14 @@ struct ftrace_likely_data { > #define notrace __attribute__((no_instrument_function)) > #endif > > +/* > + * it doesn't make sense on ARM (currently the only user of __naked) > + * to trace naked functions because then mcount is called without > + * stack and frame pointer being set up and there is no chance to > + * restore the lr register to the value before mcount was called. > + */ > +#define __naked __attribute__((naked)) notrace > + > #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) > > /*