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=-9.0 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 6ED0FC43387 for ; Mon, 31 Dec 2018 07:20:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 48E9321019 for ; Mon, 31 Dec 2018 07:20:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727091AbeLaHUi (ORCPT ); Mon, 31 Dec 2018 02:20:38 -0500 Received: from ex13-edg-ou-002.vmware.com ([208.91.0.190]:25217 "EHLO EX13-EDG-OU-002.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726442AbeLaHUi (ORCPT ); Mon, 31 Dec 2018 02:20:38 -0500 Received: from sc9-mailhost3.vmware.com (10.113.161.73) by EX13-EDG-OU-002.vmware.com (10.113.208.156) with Microsoft SMTP Server id 15.0.1156.6; Sun, 30 Dec 2018 23:20:33 -0800 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 B0C1140AE5; Sun, 30 Dec 2018 23:20:35 -0800 (PST) From: Nadav Amit To: Ingo Molnar , Andy Lutomirski , Peter Zijlstra , Josh Poimboeuf , Edward Cree CC: "H . Peter Anvin" , Thomas Gleixner , LKML , Nadav Amit , X86 ML , Paolo Abeni , Borislav Petkov , David Woodhouse , Nadav Amit Subject: [RFC v2 4/6] x86: interface for accessing indirect branch locations Date: Sun, 30 Dec 2018 23:21:10 -0800 Message-ID: <20181231072112.21051-5-namit@vmware.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181231072112.21051-1-namit@vmware.com> References: <20181231072112.21051-1-namit@vmware.com> MIME-Version: 1.0 Content-Type: text/plain Received-SPF: None (EX13-EDG-OU-002.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/sections.h | 2 ++ include/linux/module.h | 9 +++++++++ kernel/module.c | 8 ++++++++ 3 files changed, 19 insertions(+) diff --git a/arch/x86/include/asm/sections.h b/arch/x86/include/asm/sections.h index 8ea1cfdbeabc..acba39349f46 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 optpoline_entry __optpolines[], __optpolines_end[]; #endif #endif /* _ASM_X86_SECTIONS_H */ diff --git a/include/linux/module.h b/include/linux/module.h index fce6b4335e36..2590719dd8f2 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -40,6 +40,8 @@ struct modversion_info { struct module; struct exception_table_entry; +struct optpoline_entry; +struct optpoline; struct module_kobject { struct kobject kobj; @@ -387,6 +389,13 @@ struct module { unsigned int num_exentries; struct exception_table_entry *extable; +#ifdef CONFIG_OPTPOLINE + /* Dynamic indirect branch promotion */ + struct optpoline_entry *optpoline_entries; + struct optpoline *optpolines; + unsigned int num_optpolines; +#endif + /* Startup function. */ int (*init)(void); diff --git a/kernel/module.c b/kernel/module.c index 99b46c32d579..5e9edca9bbdc 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_OPTPOLINE + mod->optpoline_entries = section_objs(info, "__optpolines", + sizeof(*mod->optpoline_entries), + &mod->num_optpolines); +#endif + if (section_addr(info, "__obsparm")) pr_warn("%s: Ignoring obsolete parameters\n", mod->name); -- 2.17.1