[{"id":3675356,"web_url":"http://patchwork.ozlabs.org/comment/3675356/","msgid":"<5cf1d83227fd5a6af784f0b11fcdebf9a0bc9f94.camel@sipsolutions.net>","list_archive_url":null,"date":"2026-04-09T14:47:32","subject":"Re: [PATCH v3] gcov: Disable GCOV_PROFILE_ALL on 32-bit UML with\n Clang 20/21","submitter":{"id":265,"url":"http://patchwork.ozlabs.org/api/people/265/","name":"Johannes Berg","email":"johannes@sipsolutions.net"},"content":"Hi,\n\nMaybe the subject should say \"um:\" instead of \"gcov:\" now?\n\n(I'm assuming you want us to apply it to uml tree.)\n\n> Prevent the bad combination by disabling UML's ARCH_HAS_GCOV_PROFILE_ALL\n> on 32-bit when using Clang 20.x or 21.x.\n\nYou say 20.x or 21.x,\n\n> +\t# Clang 20 & 21 miscompute __builtin_object_size() under -fprofile-arcs\n> +\t# on 32-bit, causing spurious compile-time errors in check_copy_size().\n> +\tselect ARCH_HAS_GCOV_PROFILE_ALL if !(!64BIT && CLANG_VERSION >= 200000 && CLANG_VERSION < 220100)\n\nand I see that 22.0 doesn't even exist, and maybe that's a general\npattern, but it still looks confusing? Wouldn't it be better simpler to\nsay < 220000? At least to me that more obviously is \"up to 21.x\". After\nall, 20.0 also didn't exist, and you did >=200000, not >200000 or\n>=200100?\n\njohannes","headers":{"Return-Path":"\n ","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n secure) header.d=lists.infradead.org header.i=@lists.infradead.org\n header.a=rsa-sha256 header.s=bombadil.20210309 header.b=OloF115n;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n secure) header.d=sipsolutions.net header.i=@sipsolutions.net\n header.a=rsa-sha256 header.s=mail header.b=Y9nZ3aZX;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=none (no SPF record) smtp.mailfrom=lists.infradead.org\n (client-ip=2607:7c80:54:3::133; helo=bombadil.infradead.org;\n envelope-from=linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org;\n receiver=patchwork.ozlabs.org)"],"Received":["from bombadil.infradead.org (bombadil.infradead.org\n [IPv6:2607:7c80:54:3::133])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4fs2q01nbWz1yCv\n\tfor ; Fri, 10 Apr 2026 00:47:53 +1000 (AEST)","from localhost ([::1] helo=bombadil.infradead.org)\n\tby bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux))\n\tid 1wAqff-0000000AjMv-2b5b;\n\tThu, 09 Apr 2026 14:47:51 +0000","from s3.sipsolutions.net ([2a01:4f8:242:246e::2]\n helo=sipsolutions.net)\n\tby bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux))\n\tid 1wAqfa-0000000AjL8-2yzn\n\tfor linux-um@lists.infradead.org;\n\tThu, 09 Apr 2026 14:47:48 +0000","by sipsolutions.net with esmtpsa\n (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256)\n\t(Exim 4.98.2)\n\t(envelope-from )\n\tid 1wAqfN-0000000G2eD-3CNn;\n\tThu, 09 Apr 2026 16:47:33 +0200"],"DKIM-Signature":["v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;\n\td=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help\n\t:List-Post:List-Archive:List-Unsubscribe:List-Id:MIME-Version:\n\tContent-Transfer-Encoding:Content-Type:References:In-Reply-To:Date:Cc:To:From\n\t:Subject:Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:\n\tResent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner;\n\tbh=vtWvECdJsOce5KQBkQ6BB16WnHR2lmUFEE8FNue2MfA=; b=OloF115nAeofaywWE9Z8Xpb8sp\n\t96FEUtgipZkuXNaVE7CPxtScDt0/iMmWjhbgnftpxKokZUr0HSCXRMx4T3wcS6LmbZgsmFdnCVE5b\n\t2ulFQpGkVug5vno+pfZ0AZK28V7lM+/vnI26seaTH4GA5c//P+/VhIYMjGj5S61+FanOV65Q8Jj/7\n\tHpd7iBvcUguocGcais/zCzbOaeE56fMFFHpdnhlWP+MBd3eW2Mzs04ElH0xq094LqxMFKbcJPPe26\n\t0nM3O0fN1TAt6fdqGx2YcgYcrpaiUOTdr//D77C7C9E4F3HoJ1pe+uqXx6IB8o2pGTRK2FG4IHLqI\n\tD32T4HXQ==;","v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;\n\td=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding:\n\tContent-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender\n\t:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To:\n\tResent-Cc:Resent-Message-ID; bh=vtWvECdJsOce5KQBkQ6BB16WnHR2lmUFEE8FNue2MfA=;\n\tt=1775746066; x=1776955666; b=Y9nZ3aZXL84eklteleQagr5/yKCru9IJbxiTW93Akva6F6c\n\tO97wqTp+KnfuGJZJDAfiJpCW3tP346syGhzwN39TM4QIjhifoGTuATCwOVZFfcTusBNek/GzWjOcO\n\t4B6AD7F9lkWI8wosGaq8mqfXLrFNw/jBBc+cFxKrq2wkWGilx0WT896kf1vQagMWuQOe8LY01stJw\n\tT87r98ushe7T/exjFZRiP4D94XY59Pz5p4Ym0Xjg2lg0WFruSANIW1QcuZiE+uvJhTRZOVkxUSFjH\n\t8iySGUlp6hNCG376LuhJTQJLUWps7u79d3xWEkUj9O8PJF2uoRb+XfVrRhCQtICA==;"],"Message-ID":"<5cf1d83227fd5a6af784f0b11fcdebf9a0bc9f94.camel@sipsolutions.net>","Subject":"Re: [PATCH v3] gcov: Disable GCOV_PROFILE_ALL on 32-bit UML with\n Clang 20/21","From":"Johannes Berg ","To":"Kees Cook , Richard Weinberger ","Cc":"kernel test robot , Nathan Chancellor\n , Anton Ivanov , Peter\n Oberparleiter , Nick Desaulniers\n , Bill Wendling , Justin\n Stitt\t , llvm@lists.linux.dev,\n linux-um@lists.infradead.org, \tlinux-kernel@vger.kernel.org,\n linux-hardening@vger.kernel.org","Date":"Thu, 09 Apr 2026 16:47:32 +0200","In-Reply-To":"<20260409052038.make.995-kees@kernel.org>","References":"<20260409052038.make.995-kees@kernel.org>","Content-Type":"text/plain; charset=\"UTF-8\"","Content-Transfer-Encoding":"quoted-printable","User-Agent":"Evolution 3.58.3 (3.58.3-1.fc43) ","MIME-Version":"1.0","X-malware-bazaar":"not-scanned","X-CRM114-Version":"20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 ","X-CRM114-CacheID":"sfid-20260409_074746_748137_0B5EDB44 ","X-CRM114-Status":"UNSURE ( 7.24 )","X-CRM114-Notice":"Please train this message.","X-Spam-Score":"-2.1 (--)","X-Spam-Report":"Spam detection software,\n running on the system \"bombadil.infradead.org\",\n has NOT identified this incoming email as spam. The original\n message has been attached to this so you can view it or label\n similar future email. If you have any questions, see\n the administrator of that system for details.\n Content preview: Hi, Maybe the subject should say \"um:\" instead of \"gcov:\"\n now? (I'm assuming you want us to apply it to uml tree.)\n Content analysis details: (-2.1 points, 5.0 required)\n pts rule name description\n ---- ----------------------\n --------------------------------------------------\n -0.0 SPF_PASS SPF: sender matches SPF record\n -0.0 SPF_HELO_PASS SPF: HELO matches SPF record\n -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from\n envelope-from domain\n 0.1 DKIM_SIGNED Message has a DKIM or DK signature,\n not necessarily valid\n -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from\n author's\n domain\n -0.1 DKIM_VALID Message has at least one valid DKIM or DK\n signature\n -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1%\n [score: 0.0000]","X-BeenThere":"linux-um@lists.infradead.org","X-Mailman-Version":"2.1.34","Precedence":"list","List-Id":"","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Sender":"\"linux-um\" ","Errors-To":"linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org"}},{"id":3675452,"web_url":"http://patchwork.ozlabs.org/comment/3675452/","msgid":"<20260409182620.GA2550473@ax162>","list_archive_url":null,"date":"2026-04-09T18:26:20","subject":"Re: [PATCH v3] gcov: Disable GCOV_PROFILE_ALL on 32-bit UML with\n Clang 20/21","submitter":{"id":81040,"url":"http://patchwork.ozlabs.org/api/people/81040/","name":"Nathan Chancellor","email":"nathan@kernel.org"},"content":"On Thu, Apr 09, 2026 at 04:47:32PM +0200, Johannes Berg wrote:\n> Hi,\n> \n> Maybe the subject should say \"um:\" instead of \"gcov:\" now?\n> \n> (I'm assuming you want us to apply it to uml tree.)\n> \n> > Prevent the bad combination by disabling UML's ARCH_HAS_GCOV_PROFILE_ALL\n> > on 32-bit when using Clang 20.x or 21.x.\n> \n> You say 20.x or 21.x,\n> \n> > +\t# Clang 20 & 21 miscompute __builtin_object_size() under -fprofile-arcs\n> > +\t# on 32-bit, causing spurious compile-time errors in check_copy_size().\n> > +\tselect ARCH_HAS_GCOV_PROFILE_ALL if !(!64BIT && CLANG_VERSION >= 200000 && CLANG_VERSION < 220100)\n> \n> and I see that 22.0 doesn't even exist, and maybe that's a general\n> pattern, but it still looks confusing? Wouldn't it be better simpler to\n> say < 220000? At least to me that more obviously is \"up to 21.x\". After\n> all, 20.0 also didn't exist, and you did >=200000, not >200000 or\n> >=200100?\n\n22.0.0 means a development cycle version of LLVM 22, whereas 22.1.0 is\nthe released version (mirroring how GCC versioning works). The bug was\nnot fixed in the 22 development cycle, it was fixed at the beginning of\nthe 23 development cycle then backported to 22.1.0 before the final\nrelease, so I think the bounds is correct as it is. We assume all\nversions of 20 and 21 and the development version of 22 have the bug.\n\nCheers,\nNathan","headers":{"Return-Path":"\n ","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n secure) header.d=lists.infradead.org header.i=@lists.infradead.org\n header.a=rsa-sha256 header.s=bombadil.20210309 header.b=cPt6nU36;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=YZQ2+rBx;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=none (no SPF record) smtp.mailfrom=lists.infradead.org\n (client-ip=2607:7c80:54:3::133; helo=bombadil.infradead.org;\n envelope-from=linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org;\n receiver=patchwork.ozlabs.org)"],"Received":["from bombadil.infradead.org (bombadil.infradead.org\n [IPv6:2607:7c80:54:3::133])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4fs7gD6lqnz1yCv\n\tfor ; Fri, 10 Apr 2026 04:26:32 +1000 (AEST)","from localhost ([::1] helo=bombadil.infradead.org)\n\tby bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux))\n\tid 1wAu5G-0000000B5mI-2AQu;\n\tThu, 09 Apr 2026 18:26:30 +0000","from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25])\n\tby bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux))\n\tid 1wAu5D-0000000B5lS-41NF\n\tfor linux-um@lists.infradead.org;\n\tThu, 09 Apr 2026 18:26:29 +0000","from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58])\n\tby sea.source.kernel.org (Postfix) with ESMTP id 5CDF5409EE;\n\tThu, 9 Apr 2026 18:26:26 +0000 (UTC)","by smtp.kernel.org (Postfix) with ESMTPSA id 9CFA5C4CEF7;\n\tThu, 9 Apr 2026 18:26:23 +0000 (UTC)"],"DKIM-Signature":["v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;\n\td=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help\n\t:List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type:\n\tMIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To:\n\tContent-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:\n\tResent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner;\n\tbh=PozlKi1c5KdbUL7OKHc6/Z1RM9T1oOwBLv4Kc92LWdk=; b=cPt6nU36YiP2AF2WFZwRTM9t+Q\n\tnEBUnJwI9pZm45X85m6FSELZWKHayopqqjSwledmj3iDo6u0BpVNU6T9skNDCKLS/B/P+2W2Sa0hQ\n\tOFrG8ORDQMrlufd6fUxiORn0OO47Id+w2mHFAmvStQtmHS7ggNtkniLYjaHIKBjh6+m6EEZTyrCHV\n\tGmkIYusDzqiyiYbqvK5Nw0tiWTvAk4G+QbZwfnOfzOkleP8nPePOmP9tL61qeVY77JhdWy/09CjdB\n\tyRKp6FXFjYFFbd9cAgjkYkXIqghL9k2Wfkx7tDAVNprTAyhs/6AossBn5JPlTjZ4MrLCj/MPqUqdQ\n\twiLqjblw==;","v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1775759186;\n\tbh=A9bQ1ncAabtfS0R/KDC5j3Rw8ryqwWgMdQsEDLefxIs=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=YZQ2+rBxvWmuIce0HjdzyCT5dl8IF6I19g+TmFN0ObVDlIwajMODXNLhWJoZVVbWo\n\t v4H5Qcj0hK6FekJowIPUhOPY3DxwycXhV6o/1JApGpJZ6LU3sCjML6D7p0Kk1LbgS8\n\t Owia3/628zTQCzHFkzbW8dqrwj+bHeoVngT0jcJ47hY+50U8ejSZMw9CaLALPP7PLz\n\t dYFVmY35XVtYB3Y+lxcLhV2d9xG+Bc7CX3oCRRGzIAYbwXnoh8faQ8ehrXTDAdtwm9\n\t BJmEK5biDnMt6J0tAcswILZnIcM5Yzam/P+ul95i+Yw9YZAimdJ+Qrhk6teyQjH+V7\n\t bk30wz/a8909Q=="],"Date":"Thu, 9 Apr 2026 11:26:20 -0700","From":"Nathan Chancellor ","To":"Johannes Berg ","Cc":"Kees Cook , Richard Weinberger ,\n\tkernel test robot ,\n\tAnton Ivanov ,\n\tPeter Oberparleiter ,\n\tNick Desaulniers ,\n\tBill Wendling ,\n\tJustin Stitt , llvm@lists.linux.dev,\n\tlinux-um@lists.infradead.org, linux-kernel@vger.kernel.org,\n\tlinux-hardening@vger.kernel.org","Subject":"Re: [PATCH v3] gcov: Disable GCOV_PROFILE_ALL on 32-bit UML with\n Clang 20/21","Message-ID":"<20260409182620.GA2550473@ax162>","References":"<20260409052038.make.995-kees@kernel.org>\n <5cf1d83227fd5a6af784f0b11fcdebf9a0bc9f94.camel@sipsolutions.net>","MIME-Version":"1.0","Content-Type":"text/plain; charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"<5cf1d83227fd5a6af784f0b11fcdebf9a0bc9f94.camel@sipsolutions.net>","X-CRM114-Version":"20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 ","X-CRM114-CacheID":"sfid-20260409_112628_042625_D22DD692 ","X-CRM114-Status":"GOOD ( 14.88 )","X-Spam-Score":"-2.6 (--)","X-Spam-Report":"Spam detection software,\n running on the system \"bombadil.infradead.org\",\n has NOT identified this incoming email as spam. The original\n message has been attached to this so you can view it or label\n similar future email. If you have any questions, see\n the administrator of that system for details.\n Content preview: On Thu, Apr 09, 2026 at 04:47:32PM +0200,\n Johannes Berg wrote:\n > Hi, > > Maybe the subject should say \"um:\" instead of \"gcov:\" now? > >\n (I'm assuming you want us to apply it to uml tree.) > > > Preven [...]\n Content analysis details: (-2.6 points, 5.0 required)\n pts rule name description\n ---- ----------------------\n --------------------------------------------------\n -0.0 SPF_PASS SPF: sender matches SPF record\n 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record\n -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from\n envelope-from domain\n 0.1 DKIM_SIGNED Message has a DKIM or DK signature,\n not necessarily valid\n -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from\n author's\n domain\n -0.1 DKIM_VALID Message has at least one valid DKIM or DK\n signature\n -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1%\n [score: 0.0000]\n -0.5 DKIMWL_WL_HIGH DKIMwl.org - High trust sender","X-BeenThere":"linux-um@lists.infradead.org","X-Mailman-Version":"2.1.34","Precedence":"list","List-Id":"","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Sender":"\"linux-um\" ","Errors-To":"linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org"}}]