From patchwork Thu Sep 3 20:30:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11754879 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8969E1874 for ; Thu, 3 Sep 2020 20:35:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F88420639 for ; Thu, 3 Sep 2020 20:35:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="bl8y7IQF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729557AbgICUfe (ORCPT ); Thu, 3 Sep 2020 16:35:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729481AbgICUcr (ORCPT ); Thu, 3 Sep 2020 16:32:47 -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 E3BE4C0619EA for ; Thu, 3 Sep 2020 13:31:30 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id b127so3980818ybh.21 for ; Thu, 03 Sep 2020 13:31:30 -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=eXyK7J9+wEoy6n93pGjsemhSapgcmFl0BX/NaB/p9Jk=; b=bl8y7IQFLGNeyUAeZcfI04liBm2+5Zu2fhovRckS3HbShVs/pKY6yijYdoZGgjXbe9 rnxHlZIFkhdAC3UL0J1KPXOl/qNLi62/6WiZKWSWivwBFIdb1nS7FU25EYtuAYUJmGv8 +qz++Je0zhFE7opCb1BqdwzM2IDaUvm0cTqiaobW/Sp0ZiEVR2t6jKZvd+n2Cqqzbh8Y kwXyVj1GLGn4l5bafljvZKOUNQdm4i+Il6qu14szG7RRqeufJYl6I/DnRE+ba3CTgsG4 QlyOJKGfXIwTRIG9BHfsdwEpvtfi7qErAYGP0+FUfzucydQmKqVh5VMxBUoKCqntz4Ew 9X3w== 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=eXyK7J9+wEoy6n93pGjsemhSapgcmFl0BX/NaB/p9Jk=; b=LASNDaH+I88pMNu5F+ghBH4DDYPCqZO9PXmtj+Iy/CyAllo72ssrrtF2bfFoHnkzEw avaKFbUsSCMczLvTZBNRnqw+TmLdYEC79j9htcLcnLHsgIi75seOXvptgQ8l56MLhTXj PNmhgWFGkNiurTsM7SE3sZ1OsDlHK2dEMpGyKZxeP3nc7ylo641hdY/vGa0UkDgskAy/ ThI7tMillBe7tmDrB2S7YbVGT4txx/dFxJK7wMduXQmVXkyQwtEZEzK7mjvuZX/7JMGg ydjvRCA4Q5jY4CBiBhBTamwvyjMtpO5Fy0T2JV397iTal5MuhvW3yi+N9qHD5F9VBJnw fuqw== X-Gm-Message-State: AOAM532FWF3ZuOhWR/jQlpAqSAQ9bYYk+yLS6cZECRUSV8PKD9//C/OU 7mFsiQD4/ADynzSFbiEWdBscqVOw3PWnNqbonuA= X-Google-Smtp-Source: ABdhPJzL5rJmpcBKWDSFuqkgaUQFoP665rSkqnN6Fo73XdVlItxzzwLHKRC84PR6feaowJ2duaBg4X7jp0x4RA6WkXE= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:aab1:: with SMTP id t46mr4799689ybi.249.1599165090093; Thu, 03 Sep 2020 13:31:30 -0700 (PDT) Date: Thu, 3 Sep 2020 13:30:42 -0700 In-Reply-To: <20200903203053.3411268-1-samitolvanen@google.com> Message-Id: <20200903203053.3411268-18-samitolvanen@google.com> Mime-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> <20200903203053.3411268-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.526.ge36021eeef-goog Subject: [PATCH v2 17/28] PCI: Fix PREL32 relocations for LTO From: Sami Tolvanen To: Masahiro Yamada , Will Deacon Cc: Peter Zijlstra , Steven Rostedt , 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 Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@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, \