From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 92F1FC79FBF for ; Thu, 10 Sep 2026 15:43:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=+RU+Ljubqf1Pklfm0YOw5l6BjcrWSTHtPOZ+3ktymbw=; b=a2H2/7630vBmWSgw/i60gmRXMZ QPQPczKRsAKtz6PE+HA2Yb2RO9FNsHHXMR6CqdNANnZwk409Zr83x6XoqgvFSUSpR22LdTR03jHeo ijky+7TRmuyY9tS0ZiBWWPNFOyDCY6c24+cgvpXuBMt83e37AG9EPAsnGynUI7nb6gFjoD4HNEInm V4M27hvbmTM1pZxQ2HPZMusWFdQrE8HjHHfj9XFOA8OgSfem1tu4WJ0cwLRyKWzLHCBN8r2ZbivjM qBYRhIZ0t1KCSdArDsMISszsy9mdA47ZJqAXRPmXmU1XyiifqAsOKRmpszVCs+cE/8XfaC/AtM1MP 1g/D+6CA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x4gvJ-0000000EqOr-37x6; Thu, 10 Sep 2026 15:42:49 +0000 Received: from mail.avm.de ([212.42.244.94]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x4gvG-0000000EqLN-1QBE; Thu, 10 Sep 2026 15:42:48 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=fritz.com; s=mail; t=1789054956; bh=LK8bkV1Vz0floem0tDs4fowSkN+VH/bI8JorqlPfxFI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=m2t/gCBQ5Ji+klRB77okzADkIBpOjucABpFdn1joI6CGFroNQ2dok89iTW7zlsgDJ OhupApf9LKIRvcGE2XGbdgRc1L/Cyu778E8qiCt5Mx3N/HSwPKfTDWrLuQBULuYETh DEpZTMKIWNIB95kcOEYyM+KTdXBA1kly0af9dVc2J1yCQpvugpbSIq04iHmdW/EGZ3 Y4A/qaU5/ks6TeFtBhGFS/mS3OdzSq+oJRGgjHfaRsaS82LquTqTSeUDZk3Yd/dQog lg48YsTm0IrzSWtTPbK8Ble4vH9U4bTyk8isOlH6ribTe1cTR6+aKHV2VGyYR9cK7K zTVgF+ct8Jfhw== Received: from [212.42.244.78] (helo=mail.avm.de) by mail.avm.de with ESMTP (eXpurgate 4.57.1) (envelope-from ) id 6aa2cfec-6dc7-7f0000032729-7f000001a7b2-1 for ; Thu, 10 Sep 2026 17:42:36 +0200 Received: from mail-auth.fritz.com (unknown [212.42.244.78]) by mail.avm.de (Postfix) with ESMTPS; Thu, 10 Sep 2026 17:42:36 +0200 (CEST) Date: Thu, 10 Sep 2026 17:42:35 +0200 From: Nicolas Schier To: Nathan Chancellor Cc: "Lorenzo Stoakes (ARM)" , Linus Torvalds , Nick Desaulniers , Bill Wendling , Justin Stitt , Masahiro Yamada , Alexey Gladkov , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Arnd Bergmann , Catalin Marinas , Will Deacon , Mark Rutland , Ard Biesheuvel , Ilias Apalodimas , Josh Poimboeuf , Peter Zijlstra , Miguel Ojeda , Boqun Feng , Gary Guo , =?utf-8?B?QmrDtnJu?= Roy Baron , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , Daniel Almeida , Tamir Duberstein , Alexandre Courbot , Onur =?utf-8?B?w5Z6a2Fu?= , Jonathan Corbet , Randy Dunlap , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-efi@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-doc@vger.kernel.org, Jens Axboe Subject: Re: [PATCH 12/23] kbuild: avoid re-running compiler and linker probes Message-ID: <20260910-translucent-sweet-sidewinder-7acacb@l-nschier-aarch64> References: <20260908-build-speedup-v1-0-5dc1ac01672d@kernel.org> <20260908-build-speedup-v1-12-5dc1ac01672d@kernel.org> <178901395292.3971858.13236774094648272066.b4-review@b4> MIME-Version: 1.0 In-Reply-To: <178901395292.3971858.13236774094648272066.b4-review@b4> Organization: FRITZ! Technology GmbH x-ms-reactions: disallow X-purgate-ID: 149429::1789054956-F1CDF0BC-4895A414/0/0 X-purgate-type: clean X-purgate-size: 2705 X-Notice: Whitelisted X-purgate: This mail is considered clean (visit https://www.eleven.de for further information) X-purgate: clean X-pfmilter: host: postfix-mx-03 mail-id: 9AB3CA045E external: no X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260910_084246_530072_22F8234E X-CRM114-Status: GOOD ( 17.13 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============0524538675177290970==" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org --===============0524538675177290970== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="6NJv2EjhorC/TYUZ" Content-Disposition: inline --6NJv2EjhorC/TYUZ Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Sep 09, 2026 at 09:19:12PM -0700, Nathan Chancellor wrote: > > diff --git a/init/Kconfig b/init/Kconfig > > index 8583d9f06c52..3c92c87254a3 100644 > > --- a/init/Kconfig > > +++ b/init/Kconfig > > @@ -144,6 +144,44 @@ config CC_HAS_ASSUME > > config CC_HAS_NO_PROFILE_FN_ATTR > > def_bool $(success,echo '__attribute__((no_profile_instrument_functio= n)) int x();' | $(CC) -x c - -c -o /dev/null -Werror) > > =20 > > +config CC_HAS_ZERO_INIT_PADDING_BITS > > + def_bool $(cc-option,-fzero-init-padding-bits=3Dall) > > + > > +config CC_HAS_NO_STACK_CLASH_PROTECTION > > + def_bool $(cc-option,-fno-stack-clash-protection) > > + > > +config CC_HAS_NO_ADDRSIG > > + def_bool $(cc-option,-fno-addrsig) >=20 > I am generally in favor of this proposal since I think these checks > should be cached by Kconfig where possible to clear up running them > twice. That said, I wonder if we should pick a better dumping ground for > these checks other than init/Kconfig. Maybe init/Kconfig.tools or > scripts/Kconfig.tools or something? Yes, skimming through the patch, I thought about that, too. Moving more=20 cc option checks to Kconfig will make building out-of-tree kmods with a=20 different compiler more dangerous. Maybe we will have to make the=20 warning in Makefile's prepare (external kmods) target a bit louder. > I also worry about backsliding and growing cc-option checks. Should we > update the documentation to state that it is preferrable for these > checks to live in Kconfig so that they can be properly cached? Sounds good, yes. --=20 Nicolas --6NJv2EjhorC/TYUZ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEDv+Fiet06YHnC6RpiMa8nIiabbgFAmqiz+cACgkQiMa8nIia bbgNERAAgCLMWkWnCF5POqjQiZGkZbm/i9SwwH2BVVg0H8Bf+O6WGCZ4YiM0NOu7 6d9EZV95NkDD36Y3vCEaq1/GclFeUn2ET6HEprS7tQsmYbcofxLYoQuMV/5Si/18 jJBz3eksIZYRAnSFGG6K1+Hq3u63l3cV5TmRaquZg76LwJkTjCNsFmfT2wxHP40y LmkyOsw9NiHo2Bm75Bz8ds7EVqHU/wPxCAWBuiw6ervOrw4RR7PURz61DaBGIuOc 9B/HnhACn44debha9z9dUTsDIsPsK2sftFLfgJvD8c1V8vj6D1uhX7Fx/hXRElRA srsyf2q67EuQ8hKIU8sch6rKkD9slQJd0/w2XNQsONffnO9RghF+Qu8dzo9mUusZ l1vYg30SglV5c7m1FlgCvvmvJSppryu6zZw4FgzOUTfcxt6l+VXTm9jaigCWPXbT KAYgvQqNVVgkIAg2WDqyiVTeWQxrxo9ctf3m/6srxI4/AkuGZV/XU2m1QiQJxQ5/ rdm3WGYjD/gVrLPBr6oIoPWDSgP7C4U4kSuZGq1jWAhPeqaa691z+Z5WbRVoVDO/ SEc1cIdDE88/z8QwIEsgmaXaVhnaCiW66Npfh9zP1J+/pQV3kvU4kf9CIEQ6QMDf MPfl1Si0rJA9thzauvNi6Mu6JsUi9FPz7+Oen1Y22eMfv2st6Sc= =TUj9 -----END PGP SIGNATURE----- --6NJv2EjhorC/TYUZ-- --===============0524538675177290970== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv --===============0524538675177290970==--