Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 22 Jun 2021 11:33:24 +0200
From:   Heiko Carstens <hca@linux.ibm.com>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Kees Cook <keescook@chromium.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Bill Wendling <wcw@google.com>,
        Sami Tolvanen <samitolvanen@google.com>,
        Peter Oberparleiter <oberpar@linux.ibm.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Luc Van Oostenryck <luc.vanoostenryck@gmail.com>,
        Ard Biesheuvel <ardb@kernel.org>,
        Will Deacon <will@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com,
        x86@kernel.org, Borislav Petkov <bp@alien8.de>,
        Martin Liska <mliska@suse.cz>, Marco Elver <elver@google.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Fangrui Song <maskray@google.com>, linux-doc@vger.kernel.org,
        linux-kbuild@vger.kernel.org, Dmitry Vyukov <dvyukov@google.com>,
        johannes.berg@intel.com, linux-toolchains@vger.kernel.org,
        Vasily Gorbik <gor@linux.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        linux-s390@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        Catalin Marinas <catalin.marinas@arm.com>
Subject: Re: [PATCH v2 3/3] Kconfig: add
 ARCH_WANTS_NO_INSTR+CC_HAS_NO_PROFILE_FN_ATTR, depend on for GCOV and PGO
Message-ID: <YNGuZPl64IwQeF0/@osiris>
References: <20210621231822.2848305-1-ndesaulniers@google.com>
 <20210621231822.2848305-4-ndesaulniers@google.com>
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210621231822.2848305-4-ndesaulniers@google.com>
MIME-Version: 1.0
Precedence: bulk

On Mon, Jun 21, 2021 at 04:18:22PM -0700, Nick Desaulniers wrote:
> We don't want compiler instrumentation to touch noinstr functions, which
> are annotated with the no_profile_instrument_function function
> attribute. Add a Kconfig test for this and make PGO and GCOV depend on
> it.
> 
> If an architecture is using noinstr, it should denote that via this
> Kconfig value. That makes Kconfigs that depend on noinstr able to
> express dependencies in an architecturally agnostic way.
> 
> Cc: Masahiro Yamada <masahiroy@kernel.org>
> Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
> Link: https://lore.kernel.org/lkml/YMTn9yjuemKFLbws@hirez.programming.kicks-ass.net/
> Link: https://lore.kernel.org/lkml/YMcssV%2Fn5IBGv4f0@hirez.programming.kicks-ass.net/
> Suggested-by: Nathan Chancellor <nathan@kernel.org>
> Suggested-by: Peter Zijlstra <peterz@infradead.org>
> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
> ---
> Changes V1 -> V2:
> * Add ARCH_WANTS_NO_INSTR
> * Change depdendencies to be !ARCH_WANTS_NO_INSTR || CC_HAS_NO_PROFILE_FN_ATTR
>   rather than list architectures explicitly, as per Nathan.
> * s/no_profile/no_profile_instrument_function/
> 
>  arch/Kconfig        | 7 +++++++
>  arch/arm64/Kconfig  | 1 +
>  arch/s390/Kconfig   | 1 +
>  arch/x86/Kconfig    | 1 +
>  init/Kconfig        | 3 +++
>  kernel/gcov/Kconfig | 1 +
>  kernel/pgo/Kconfig  | 3 ++-
>  7 files changed, 16 insertions(+), 1 deletion(-)

For s390:
Acked-by: Heiko Carstens <hca@linux.ibm.com>