From patchwork Tue Oct 13 00:31:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834839 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 5D45F17D1 for ; Tue, 13 Oct 2020 02:45:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 41A1420678 for ; Tue, 13 Oct 2020 02:45:38 +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 S1727639AbgJMAer (ORCPT ); Mon, 12 Oct 2020 20:34:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727634AbgJMAdM (ORCPT ); Mon, 12 Oct 2020 20:33:12 -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 A1796C0613E9 for ; Mon, 12 Oct 2020 17:32:43 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id m62so15541382ybb.6 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=ilariCvGhqORAzIQuPOpO7AXBX0aBjcNnQ/LZVSLTZAi+ol48PWmRRQInCXCuubcOA tUBdT1FA3nHyEF4C0CRZPGEojO/m7QXdl3EP8uvUEW0cIxjPIoTfChkX07gnwfS+xmRd si8SyYVI5n7X3n57UJuxrdruuYzTD9ULXxJp+5Gy1NpXe8fqgeRzUrbegstpo8Id+HZg CFrT8WU1+S3+eG9NDuAIHrh1J/iZRvQuvtd9RNlLxq5lL9W1HE6KKUUi+/ztIt4ATZQJ fOp/Ss9RPdRwA12/4NMxDCb1eLbtqlFFd+ridNpREppeNUoxmW1ZAwZPU91TJT0trjhQ OYdA== X-Gm-Message-State: AOAM532ROUw9zc6zTOIpWqV55SEsALSyHdReXPx3eK0WwOsUVbocfzig Kf0VjPe7q65BoRuBPOO/owZO8CgQvG83Y9oBIDM= 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 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, \