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 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=unavailable 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 1605CC63697 for ; Tue, 13 Oct 2020 02:42:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D93C0221FC for ; Tue, 13 Oct 2020 02:42:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="MykYLsVo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727822AbgJMAew (ORCPT ); Mon, 12 Oct 2020 20:34:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727191AbgJMAdL (ORCPT ); Mon, 12 Oct 2020 20:33:11 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A037CC0613E8 for ; Mon, 12 Oct 2020 17:32:43 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id a7so19056355ybq.22 for ; Mon, 12 Oct 2020 17:32:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=b5rCnYz4obhAgpKHq4mgEn5Hvv5UPGIbAlGkTv5aKg4=; b=MykYLsVoW6bkD+kFLc2l4bZyxZpNnxo5YIENz3yzcHdNClIoPGRyCYicb5g8AQrHlf df0Gi9/JPdft0uy6mxQ8xnHAIiPgUf/18ZfL8+WUyQb/jixQHXBLhPe7l8ku7/iBS+dk mWk3XCOGF5DUG3vDFMYT/uzcvXkm9kiXnlA1gynp2l/H8pHXYSzhOHAKpK0ZbzYicU1P frWYR08lQPhQRINUTpGAlkvjHk+GvfxvYhoX8ZHnGwBsE5Y4RkibJPqELUFCiH0ueFWl 1IdBzaLdFbnfnlmrxckdCqOEsoDhKenpLBG0Q/F1J5BC444cYLDhWDWGR3dyO2Uj2m9+ febQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=b5rCnYz4obhAgpKHq4mgEn5Hvv5UPGIbAlGkTv5aKg4=; b=jYX+pqS8j2hWKR41Pv+ANyCPneQOivpKPgo13vS0NTHAQ5JG6KsiT7ShUjU6LdJUZ7 JHMQhz2beLDH2JVxfql9X4P2VIPKm4zwZek8hkzuJ7vvOofWCm/s7AEl6UTIp4qfmO7x 173WsaIxaUiz/lDH1C0tJk5dx3h6tU+7tq4eATz0lgSSZcXDJ+t4j+PU3N+1IMG4OtX1 /PXCK4BRYztvemj9YGKac1Nzbi0O7DNdSEUXQEhZ9kolRUapBNajXli2u1so2EtpuC5f 21YPS36lYeiCVuRESDOVWZOyHvVeO3IQ9KAhs3RJDSUyVzmiMh3gnm43vz4GEVUC7Nyl YfoA== X-Gm-Message-State: AOAM5304YmC8cTp5yo57QxSS80eByRjsLZ/lWfTUBmKx6zl1rMbJCRGg 65UEyCtYBwVYJoKLc2Vxb1UpiWyAJptfHM5fRiA= X-Google-Smtp-Source: ABdhPJxj3WaxnTrI4Y+21BRW/jvruhJbF5tMQ4nUmURYi2TvGAs4d/9YZvJC9PHsI7NLcVk286bnvQSZPRgh877RCN0= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:73c9:: with SMTP id o192mr13193667ybc.353.1602549162840; Mon, 12 Oct 2020 17:32:42 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:55 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-18-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 17/25] PCI: Fix PREL32 relocations for LTO From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With Clang's Link Time Optimization (LTO), the compiler can rename static functions to avoid global naming collisions. As PCI fixup functions are typically static, renaming can break references to them in inline assembly. This change adds a global stub to DECLARE_PCI_FIXUP_SECTION to fix the issue when PREL32 relocations are used. Signed-off-by: Sami Tolvanen Acked-by: Bjorn Helgaas Reviewed-by: Kees Cook --- include/linux/pci.h | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/include/linux/pci.h b/include/linux/pci.h index 835530605c0d..4e64421981c7 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1909,19 +1909,28 @@ enum pci_fixup_pass { }; #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS -#define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ - class_shift, hook) \ - __ADDRESSABLE(hook) \ +#define ___DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ + class_shift, hook, stub) \ + void stub(struct pci_dev *dev); \ + void stub(struct pci_dev *dev) \ + { \ + hook(dev); \ + } \ asm(".section " #sec ", \"a\" \n" \ ".balign 16 \n" \ ".short " #vendor ", " #device " \n" \ ".long " #class ", " #class_shift " \n" \ - ".long " #hook " - . \n" \ + ".long " #stub " - . \n" \ ".previous \n"); + +#define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ + class_shift, hook, stub) \ + ___DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ + class_shift, hook, stub) #define DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ class_shift, hook) \ __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ - class_shift, hook) + class_shift, hook, __UNIQUE_ID(hook)) #else /* Anonymous variables would be nice... */ #define DECLARE_PCI_FIXUP_SECTION(section, name, vendor, device, class, \ -- 2.28.0.1011.ga647a8990f-goog