From nobody Sun Feb 8 05:23:13 2026 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 4B5F3C001E0 for ; Wed, 2 Aug 2023 14:33:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233806AbjHBOdW (ORCPT ); Wed, 2 Aug 2023 10:33:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36174 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231795AbjHBOdU (ORCPT ); Wed, 2 Aug 2023 10:33:20 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 677221723; Wed, 2 Aug 2023 07:33:18 -0700 (PDT) Date: Wed, 02 Aug 2023 14:33:16 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1690986796; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iBsgB1YLGfdl/SuhRbFuHsRmPl5vqrv9c+Xp2VGeIns=; b=YO9grGOi6dMO5re7MmmMEkWvlIcKpXTNPZRXY9A1EJKHFhqPGRtwgveF6hX7elLOtSLdL2 8qMih6NwA8uJg0FlHlaAZwswAQfS5j+BkPc7JBHWZEATmA0ZYrg/+jTRRvTcNHTI46sUy0 JJsMH8Hb3kg0hexYTt4yL0+lwl68xhXqAScVmE568OAdhlRpvKRTSI+c3mknty4JoypMk8 vCWsAEXZLDFFgukEXfdue8rIw6aEMd4cG1SuZoskB9L+JSGLeYCbjDhjF2LeqkeIr1VST/ cRM62+zDMTugwM61R88rKorxau6OLHGb/m2VH4k3t/8MstDhHEN7quL+cX+4yA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1690986796; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iBsgB1YLGfdl/SuhRbFuHsRmPl5vqrv9c+Xp2VGeIns=; b=uRe1hDAh9TJSm1ycOqyQBOKXTb8CnsvlijTKGrq30Qox39Rwa7gCXALXKPLe65B7PJ6/iL +and02IxgK0+6jDw== From: "tip-bot2 for Petr Pavlu" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/core] x86/retpoline,kprobes: Fix position of thunk sections with CONFIG_LTO_CLANG Cc: Petr Pavlu , "Peter Zijlstra (Intel)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20230711091952.27944-2-petr.pavlu@suse.com> References: <20230711091952.27944-2-petr.pavlu@suse.com> MIME-Version: 1.0 Message-ID: <169098679602.28540.7005603884356771970.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/core branch of tip: Commit-ID: 973ab2d61f33dc85212c486e624af348c4eeb5c9 Gitweb: https://git.kernel.org/tip/973ab2d61f33dc85212c486e624af348c= 4eeb5c9 Author: Petr Pavlu AuthorDate: Tue, 11 Jul 2023 11:19:51 +02:00 Committer: Peter Zijlstra CommitterDate: Wed, 02 Aug 2023 16:27:07 +02:00 x86/retpoline,kprobes: Fix position of thunk sections with CONFIG_LTO_CLANG Linker script arch/x86/kernel/vmlinux.lds.S matches the thunk sections ".text.__x86.*" from arch/x86/lib/retpoline.S as follows: .text { [...] TEXT_TEXT [...] __indirect_thunk_start =3D .; *(.text.__x86.*) __indirect_thunk_end =3D .; [...] } Macro TEXT_TEXT references TEXT_MAIN which normally expands to only ".text". However, with CONFIG_LTO_CLANG, TEXT_MAIN becomes ".text .text.[0-9a-zA-Z_]*" which wrongly matches also the thunk sections. The output layout is then different than expected. For instance, the currently defined range [__indirect_thunk_start, __indirect_thunk_end] becomes empty. Prevent the problem by using ".." as the first separator, for example, ".text..__x86.indirect_thunk". This pattern is utilized by other explicit section names which start with one of the standard prefixes, such as ".text" or ".data", and that need to be individually selected in the linker script. Fixes: dc5723b02e52 ("kbuild: add support for Clang LTO") Signed-off-by: Petr Pavlu Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20230711091952.27944-2-petr.pavlu@suse.com --- arch/x86/kernel/vmlinux.lds.S | 2 +- arch/x86/lib/retpoline.S | 4 ++-- tools/objtool/check.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 03c885d..a4cd04c 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -134,7 +134,7 @@ SECTIONS SOFTIRQENTRY_TEXT #ifdef CONFIG_RETPOLINE __indirect_thunk_start =3D .; - *(.text.__x86.*) + *(.text..__x86.*) __indirect_thunk_end =3D .; #endif STATIC_CALL_TEXT diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S index 3fd066d..3bea963 100644 --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -12,7 +12,7 @@ #include #include =20 - .section .text.__x86.indirect_thunk + .section .text..__x86.indirect_thunk =20 =20 .macro POLINE reg @@ -131,7 +131,7 @@ SYM_CODE_END(__x86_indirect_jump_thunk_array) */ #ifdef CONFIG_RETHUNK =20 - .section .text.__x86.return_thunk + .section .text..__x86.return_thunk =20 /* * Safety details here pertain to the AMD Zen{1,2} microarchitecture: diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 8936a05..e096eb3 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -389,7 +389,7 @@ static int decode_instructions(struct objtool_file *fil= e) if (!strcmp(sec->name, ".noinstr.text") || !strcmp(sec->name, ".entry.text") || !strcmp(sec->name, ".cpuidle.text") || - !strncmp(sec->name, ".text.__x86.", 12)) + !strncmp(sec->name, ".text..__x86.", 12)) sec->noinstr =3D true; =20 /*