From patchwork Thu Oct 29 18:05:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fangrui Song X-Patchwork-Id: 317447 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DF642C56202 for ; Thu, 29 Oct 2020 18:11:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8482220825 for ; Thu, 29 Oct 2020 18:11:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Juj++IZc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725807AbgJ2SLv (ORCPT ); Thu, 29 Oct 2020 14:11:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725834AbgJ2SFc (ORCPT ); Thu, 29 Oct 2020 14:05:32 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83C17C0613CF for ; Thu, 29 Oct 2020 11:05:32 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id z11so2596141pln.0 for ; Thu, 29 Oct 2020 11:05:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:message-id:mime-version:subject:from:to:cc; bh=TFVBAa3RYz8IYFna+GiAaNLsKOoOUuSXlq1eujs3Qh8=; b=Juj++IZc3lSNCiiQKlsX2xGGWtciIsFGhkU/BjW/dVuczbq/r6kIb7sv+OiBmt2Fum wy3QTRkVqAQ8r6R8auKz9HldWIqqUZYndKCC5iYT63FW5zMYw+Wf5i32VZlrUP6vyeC2 PE2JmUni9inhxWko4FzPxEhTpqLDIzecIAij28IYgJkmto3eLVN3UwLjxNRhqbNFrPp9 hAyHSL0//CuYgoI3z2GhNtLCq8gQcuuONoNHmmLoFfzZ9DiqZcQc7TonASNgMFGbMhMR BOFUlZwyJZ468+Yru01BuFvxAViVHh3JCdEJTIDPrWWh7XmARQ53PjL13bfkuZlc3lZV g37w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:message-id:mime-version:subject:from :to:cc; bh=TFVBAa3RYz8IYFna+GiAaNLsKOoOUuSXlq1eujs3Qh8=; b=CnTWghI3gCZGOjlXr8ZAdsoJCT6q2u4n4L9dKPnx4rfk2qvEpEaLryNSf3tiVkdU78 x2daJMGV9Wi5IfciuX48YZkbBahWiCHAGqtachP+htyiGzTZv9fE4N+pQOdA4BrSPoz+ fb/cKBi8NanJ25/5fuwMj7w2OvsTPgTMd3Hq6MVSkekgrz7m2b+ZbeZK9qIsMYEpYjx3 s8fyaGgMK6qIHoGu+NYqEtCPjEwtabTxlg6/0rJV0XG4BSY9I2jGcfS0wFydTKho7HDR aLKlIU5IEhYPe3BDhFTeAcyBo5cr41ur3x9Xslw/KxGFzA7PaDzBSfqNrSxywrK8Jjeu e+cg== X-Gm-Message-State: AOAM533bMJ6EHVYkJoCmiGIKaVkhGYGUuwJFO3GDCNPFYT++ExYVW+H6 f9yI/bnB5vxGbSzsPl5vv9zd/cA8AM8K X-Google-Smtp-Source: ABdhPJzi7jxnbvZDKUzR8TxbeI+79bLhBWvevXZpkjf8sMsmi3CeNe4f58x0A/gxVSN7sERoUXIONJFErukz Sender: "maskray via sendgmr" X-Received: from maskray1.svl.corp.google.com ([2620:15c:2ce:0:a6ae:11ff:fe11:4abb]) (user=maskray job=sendgmr) by 2002:a62:4e0f:0:b029:156:13e0:efa7 with SMTP id c15-20020a624e0f0000b029015613e0efa7mr5285238pfb.73.1603994731999; Thu, 29 Oct 2020 11:05:31 -0700 (PDT) Date: Thu, 29 Oct 2020 11:05:25 -0700 Message-Id: <20201029180525.1797645-1-maskray@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.29.1.341.ge80a0c044ae-goog Subject: [PATCH] x86_64: Change .weak to SYM_FUNC_START_WEAK for arch/x86/lib/mem*_64.S From: Fangrui Song To: x86@kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov Cc: clang-built-linux@googlegroups.com, Jian Cai , Fangrui Song , Sami Tolvanen , stable@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Commit 393f203f5fd5 ("x86_64: kasan: add interceptors for memset/memmove/memcpy functions") added .weak directives to arch/x86/lib/mem*_64.S instead of changing the existing SYM_FUNC_START_* macros. This can lead to the assembly snippet `.weak memcpy ... .globl memcpy` which will produce a STB_WEAK memcpy with GNU as but STB_GLOBAL memcpy with LLVM's integrated assembler before LLVM 12. LLVM 12 (since https://reviews.llvm.org/D90108) will error on such an overridden symbol binding. Use the appropriate SYM_FUNC_START_WEAK instead. Fixes: 393f203f5fd5 ("x86_64: kasan: add interceptors for memset/memmove/memcpy functions") Reported-by: Sami Tolvanen Signed-off-by: Fangrui Song Cc: Tested-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers --- arch/x86/lib/memcpy_64.S | 4 +--- arch/x86/lib/memmove_64.S | 4 +--- arch/x86/lib/memset_64.S | 4 +--- 3 files changed, 3 insertions(+), 9 deletions(-) diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index 037faac46b0c..1e299ac73c86 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -16,8 +16,6 @@ * to a jmp to memcpy_erms which does the REP; MOVSB mem copy. */ -.weak memcpy - /* * memcpy - Copy a memory block. * @@ -30,7 +28,7 @@ * rax original destination */ SYM_FUNC_START_ALIAS(__memcpy) -SYM_FUNC_START_LOCAL(memcpy) +SYM_FUNC_START_WEAK(memcpy) ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \ "jmp memcpy_erms", X86_FEATURE_ERMS diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S index 7ff00ea64e4f..41902fe8b859 100644 --- a/arch/x86/lib/memmove_64.S +++ b/arch/x86/lib/memmove_64.S @@ -24,9 +24,7 @@ * Output: * rax: dest */ -.weak memmove - -SYM_FUNC_START_ALIAS(memmove) +SYM_FUNC_START_WEAK(memmove) SYM_FUNC_START(__memmove) mov %rdi, %rax diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S index 9ff15ee404a4..0bfd26e4ca9e 100644 --- a/arch/x86/lib/memset_64.S +++ b/arch/x86/lib/memset_64.S @@ -6,8 +6,6 @@ #include #include -.weak memset - /* * ISO C memset - set a memory block to a byte value. This function uses fast * string to get better performance than the original function. The code is @@ -19,7 +17,7 @@ * * rax original destination */ -SYM_FUNC_START_ALIAS(memset) +SYM_FUNC_START_WEAK(memset) SYM_FUNC_START(__memset) /* * Some CPUs support enhanced REP MOVSB/STOSB feature. It is recommended