From patchwork Fri Sep 18 20:14:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11786095 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 6F47814B7 for ; Fri, 18 Sep 2020 20:16:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4971523788 for ; Fri, 18 Sep 2020 20:16:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Qgpy+pbz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726605AbgIRUQO (ORCPT ); Fri, 18 Sep 2020 16:16:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52942 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726612AbgIRUPb (ORCPT ); Fri, 18 Sep 2020 16:15:31 -0400 Received: from mail-qk1-x749.google.com (mail-qk1-x749.google.com [IPv6:2607:f8b0:4864:20::749]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CBA41C0613DB for ; Fri, 18 Sep 2020 13:15:24 -0700 (PDT) Received: by mail-qk1-x749.google.com with SMTP id a136so2632618qkb.18 for ; Fri, 18 Sep 2020 13:15:24 -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=iG8c4IVmV6SAigaVNA/2Da1zni30786ipLEHlcLZdp4=; b=Qgpy+pbznAwuGgS1UcHWV2+GgEBqJBW/QXwkjniAUgd0yEt/iVnU3kXXwNdozhgQzz MZzhTSncTCZS90D0o8lSwmN7wmdlvsaE1QWRoTj6Wbe2nae8ffdijksuNQIIVYs/eybZ PhIUX9y2TjqMSdsaiGH0h2KtARkrrLOZf/w8Sm2VeQum5NJG1Sy6tVoqsuv4aAwEG7YK 02eRqNOcpZQaCeV7Ckrk7WrJ5FjODwlvlNCDUQkrG9fITgVhDbllmG+pZNctstR4JiRy rA0r42k8E4pddkc8iQa3ov74ZrsmEOgVOhRYMv7EwvJEm2M2DLQUQBG2GyMEcM38Vad0 xDlw== 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=iG8c4IVmV6SAigaVNA/2Da1zni30786ipLEHlcLZdp4=; b=B1WXr1qJ5wAIuf8iUYFvXX7AJ0JwzGeeLVc2+eEYVvSneA3Iu2eAxDAya7pW0Qw3Nt QAVxRt5JOd2/wwsUfzNT55NvVq3WHvJCzw0cr+TWaanISqK+B21BCiRagLHlRaIX+GZH YdL6qB7sfsoJzsQ72IfxzYbd2ZKqEJjgqIsBdIhjl2orM4b8gylizdTnBxbAPR4yOfdY rM5uQ56JkJfDCYX88wLKglNow51BiXk70Oqq47JI4p4b/fWk5GxiWyEN8m+55MyL4MuG GS63D8bjvYt1RQ8DI1lv95u6AecqXWCHUEdmTKe7EeLVca13NLULIBKb3je3rgJvFsZ4 Dhww== X-Gm-Message-State: AOAM533E8pQQMgjyYqCM6FdJlhmAm9DTjxf7dplDyxSyh0JXTK0LzloV vdAUANYEIVOU5KAnJxIObn99Kz7uppFbFfcAxMk= X-Google-Smtp-Source: ABdhPJyAaI/eiFtDj86m6e83BVMlPsjdMZNZWL0L4WJ70VEUwFhQzIrnfngpXkviQEnEmXABI7Y2dHDcYxV6d7VeWCU= 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:ad4:58c7:: with SMTP id dh7mr8337663qvb.20.1600460123968; Fri, 18 Sep 2020 13:15:23 -0700 (PDT) Date: Fri, 18 Sep 2020 13:14:25 -0700 In-Reply-To: <20200918201436.2932360-1-samitolvanen@google.com> Message-Id: <20200918201436.2932360-20-samitolvanen@google.com> Mime-Version: 1.0 References: <20200918201436.2932360-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.681.g6f77f65b4e-goog Subject: [PATCH v3 19/30] 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 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, \