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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 62D0DECDE42 for ; Thu, 18 Oct 2018 00:56:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2B3382145D for ; Thu, 18 Oct 2018 00:56:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2B3382145D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vmware.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727497AbeJRIyq (ORCPT ); Thu, 18 Oct 2018 04:54:46 -0400 Received: from ex13-edg-ou-001.vmware.com ([208.91.0.189]:46860 "EHLO EX13-EDG-OU-001.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727019AbeJRIye (ORCPT ); Thu, 18 Oct 2018 04:54:34 -0400 Received: from sc9-mailhost3.vmware.com (10.113.161.73) by EX13-EDG-OU-001.vmware.com (10.113.208.155) with Microsoft SMTP Server id 15.0.1156.6; Wed, 17 Oct 2018 17:55:41 -0700 Received: from sc2-haas01-esx0118.eng.vmware.com (sc2-haas01-esx0118.eng.vmware.com [10.172.44.118]) by sc9-mailhost3.vmware.com (Postfix) with ESMTP id 4BAD540918; Wed, 17 Oct 2018 17:56:09 -0700 (PDT) From: Nadav Amit To: Ingo Molnar CC: Andy Lutomirski , Peter Zijlstra , "H . Peter Anvin " , Thomas Gleixner , , Nadav Amit , , Borislav Petkov , David Woodhouse , Nadav Amit Subject: [RFC PATCH 3/5] x86: interface for accessing indirect branch locations Date: Wed, 17 Oct 2018 17:54:18 -0700 Message-ID: <20181018005420.82993-4-namit@vmware.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181018005420.82993-1-namit@vmware.com> References: <20181018005420.82993-1-namit@vmware.com> MIME-Version: 1.0 Content-Type: text/plain Received-SPF: None (EX13-EDG-OU-001.vmware.com: namit@vmware.com does not designate permitted sender hosts) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Adding a C interface to access the locations of indirect branches. To be used for dynamic patching. Signed-off-by: Nadav Amit --- arch/x86/include/asm/nospec-branch.h | 1 - arch/x86/include/asm/sections.h | 2 ++ include/linux/module.h | 5 +++++ kernel/module.c | 8 ++++++++ 4 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index bd2d3a41e88c..a4496c141143 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -406,7 +406,6 @@ struct relpoline_entry { u8 reg; } __packed; - /* The Intel SPEC CTRL MSR base value cache */ extern u64 x86_spec_ctrl_base; diff --git a/arch/x86/include/asm/sections.h b/arch/x86/include/asm/sections.h index 8ea1cfdbeabc..e8dd9c40ecd5 100644 --- a/arch/x86/include/asm/sections.h +++ b/arch/x86/include/asm/sections.h @@ -4,6 +4,7 @@ #include #include +#include extern char __brk_base[], __brk_limit[]; extern struct exception_table_entry __stop___ex_table[]; @@ -11,6 +12,7 @@ extern char __end_rodata_aligned[]; #if defined(CONFIG_X86_64) extern char __end_rodata_hpage_align[]; +extern const struct relpoline_entry __relpolines[], __relpolines_end[]; #endif #endif /* _ASM_X86_SECTIONS_H */ diff --git a/include/linux/module.h b/include/linux/module.h index f807f15bebbe..29ff390f8339 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -39,6 +39,7 @@ struct modversion_info { struct module; struct exception_table_entry; +struct relpoline_entry; struct module_kobject { struct kobject kobj; @@ -387,6 +388,10 @@ struct module { unsigned int num_exentries; struct exception_table_entry *extable; + /* Cachepolines */ + unsigned int num_relpolines; + struct relpoline_entry *relpolines; + /* Startup function. */ int (*init)(void); diff --git a/kernel/module.c b/kernel/module.c index 49a405891587..e34fc28875bd 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -64,6 +64,7 @@ #include #include #include +#include #include #include "module-internal.h" @@ -256,6 +257,7 @@ static void mod_update_bounds(struct module *mod) #ifdef CONFIG_KGDB_KDB struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ #endif /* CONFIG_KGDB_KDB */ +struct list_head *cachepoline_modules = &modules; static void module_assert_mutex(void) { @@ -3125,6 +3127,12 @@ static int find_module_sections(struct module *mod, struct load_info *info) mod->extable = section_objs(info, "__ex_table", sizeof(*mod->extable), &mod->num_exentries); +#ifdef CONFIG_X86_64 + mod->relpolines = section_objs(info, "__relpolines", + sizeof(*mod->relpolines), + &mod->num_relpolines); +#endif + if (section_addr(info, "__obsparm")) pr_warn("%s: Ignoring obsolete parameters\n", mod->name); -- 2.17.1