From nobody Fri Sep 12 20:11:14 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E23F9C636CC for ; Tue, 7 Feb 2023 16:14:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231411AbjBGQOJ (ORCPT ); Tue, 7 Feb 2023 11:14:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37344 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231779AbjBGQOD (ORCPT ); Tue, 7 Feb 2023 11:14:03 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C164E055 for ; Tue, 7 Feb 2023 08:13:58 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 77F46CE1DFA for ; Tue, 7 Feb 2023 16:13:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B49F3C433D2; Tue, 7 Feb 2023 16:13:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675786433; bh=DQ1CJxcjsi3b+zqgaRiU3Jl5v/BM3ICCZKlhKghFh0M=; h=From:To:Cc:Subject:Date:From; b=DE3g6e+J+twxY5iQXeiCiS+916bB/3gIK508QO16HKNA9TOuv0k/FRrTm7HPd0ktF r70sg7p3xeFPTV15xJDQPZDPq+HHpmLHcCxRq/9gb9IMRf8oGiUWG/G0O4px2hTJqW J6aQjfA6tsc2SlQkawRpi9+vdao8xyLmKUP7+v44ztj7clMM4hw+1f6QsD/LzPE5MH 6Eibdp9yNk/kfLNMzfefvhpoO4qoaO2h6HQKwCUVFCB/lB03RH8JUmSKvegtZtUVcl MltwtVrcGh/Rvth5lCojNAf0jARdFgRjn1kuBDV5CfPK5Ds/Y5xMqd06HrPQr4uDfE sxffkOhc8VIuw== From: Arnd Bergmann To: Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Nathan Chancellor , Nick Desaulniers , Sebastian Andrzej Siewior Cc: Arnd Bergmann , "H. Peter Anvin" , Tom Rix , linux-kernel@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH] x86: vdso: sanitize asm helpers for vgetcpu.c Date: Tue, 7 Feb 2023 17:13:41 +0100 Message-Id: <20230207161349.309901-1-arnd@kernel.org> X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Arnd Bergmann The x86 vdso implementation includes a few include/linux/*.h kernel headers outside of the include/vdso/*.h space. This causes a new warning when building with clang, after the vgetcpu code is added to the vdso32 support on 64-bit kernels: In file included from arch/x86/entry/vdso/vdso32/vgetcpu.c:2: In file included from arch/x86/entry/vdso/vdso32/../vgetcpu.c:8: In file included from include/linux/kernel.h:22: In file included from include/linux/bitops.h:68: In file included from arch/x86/include/asm/bitops.h:420: arch/x86/include/asm/arch_hweight.h:49:15: error: invalid input size for co= nstraint 'D' : REG_IN (w)); ^ In file included from arch/x86/entry/vdso/vdso32/vgetcpu.c:2: In file included from arch/x86/entry/vdso/vdso32/../vgetcpu.c:8: In file included from include/linux/kernel.h:25: In file included from include/linux/math.h:6: arch/x86/include/asm/div64.h:85:34: error: invalid output size for constrai= nt '=3Da' asm ("mulq %2; divq %3" : "=3Da" (q) ^ Unlike gcc, clang checks inline asm constraints before dead code elimination, which breaks both __arch_hweight64() and mul_u64_u64_div_u64() when these are included with CONFIG_64BIT set but compiled with clang -m32, even when there are no callers. Change both affected headers to the check for 32-bit vs 64-bit is done correctly for vdso32. It would be nice to also limit the included headers further, to avoid subtle differences in the header contents, but that requires a larger cleanup. Fixes: 92d33063c081 ("x86/vdso: Provide getcpu for x86-32.") Signed-off-by: Arnd Bergmann --- arch/x86/entry/vdso/vdso32/vgetcpu.c | 2 ++ arch/x86/include/asm/arch_hweight.h | 4 ++-- arch/x86/include/asm/div64.h | 2 +- 3 files changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/x86/entry/vdso/vdso32/vgetcpu.c b/arch/x86/entry/vdso/vds= o32/vgetcpu.c index b777f84ffae9..9f8cf77c7077 100644 --- a/arch/x86/entry/vdso/vdso32/vgetcpu.c +++ b/arch/x86/entry/vdso/vdso32/vgetcpu.c @@ -1,2 +1,4 @@ // SPDX-License-Identifier: GPL-2.0 +#define BUILD_VDSO32 + #include "../vgetcpu.c" diff --git a/arch/x86/include/asm/arch_hweight.h b/arch/x86/include/asm/arc= h_hweight.h index ba88edd0d58b..cca0941673e0 100644 --- a/arch/x86/include/asm/arch_hweight.h +++ b/arch/x86/include/asm/arch_hweight.h @@ -4,7 +4,7 @@ =20 #include =20 -#ifdef CONFIG_64BIT +#if defined(CONFIG_64BIT) && !defined(BUILD_VDSO32) #define REG_IN "D" #define REG_OUT "a" #else @@ -33,7 +33,7 @@ static inline unsigned int __arch_hweight8(unsigned int w) return __arch_hweight32(w & 0xff); } =20 -#ifdef CONFIG_X86_32 +#if defined(CONFIG_X86_32) || defined(BUILD_VDSO32) static inline unsigned long __arch_hweight64(__u64 w) { return __arch_hweight32((u32)w) + diff --git a/arch/x86/include/asm/div64.h b/arch/x86/include/asm/div64.h index b8f1dc0761e4..97bd076db0b2 100644 --- a/arch/x86/include/asm/div64.h +++ b/arch/x86/include/asm/div64.h @@ -2,7 +2,7 @@ #ifndef _ASM_X86_DIV64_H #define _ASM_X86_DIV64_H =20 -#ifdef CONFIG_X86_32 +#if defined(CONFIG_X86_32) || defined(BUILD_VDSO32) =20 #include #include --=20 2.39.1