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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 9A940C433E1 for ; Fri, 26 Mar 2021 15:14:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 882A361A4F for ; Fri, 26 Mar 2021 15:14:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231368AbhCZPOb (ORCPT ); Fri, 26 Mar 2021 11:14:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230434AbhCZPNo (ORCPT ); Fri, 26 Mar 2021 11:13:44 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5866C0613AA for ; Fri, 26 Mar 2021 08:13:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=lRJVuN5SNm42ulmHDQq0rFSR4dCPy/OGCrzKirUZcWE=; b=OkX5UXd5ALsR3hkMONhr1bKHXP uD0a41yz5lGik3LMA017V1XdhqvmXL0ocFZYLuQuvB8XarqDSfumOyq5p+2BgsR4rigPN7+1jANHL FHCLkLlBJEyLybnvFaxtO9S9fjJuzo3x2gJzNuAOuxeBGCb7maYKE4En/Yjeobo2J4kBhH80QDr1l aRKi8iUndQrJbnInp4K3209Ab+X5GLVGmoHlPB0FiGDeITHeAQOWZVMPl8zCIox54OC11Myt51Bcp FxF4c4jB0gPVre2y2G24/LG2Sbx00DATGw70DsDG8CBx+QT/+JbHNO6HpefK9MfsrW3PZsMcNFO+D 8rjLEB7g==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lPo9Y-003s0S-Fb; Fri, 26 Mar 2021 15:13:36 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id AF2F53079B2; Fri, 26 Mar 2021 16:13:34 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 733C32BD7339D; Fri, 26 Mar 2021 16:13:34 +0100 (CET) Message-ID: <20210326151300.130805730@infradead.org> User-Agent: quilt/0.66 Date: Fri, 26 Mar 2021 16:12:12 +0100 From: Peter Zijlstra To: x86@kernel.org, jpoimboe@redhat.com, jgross@suse.com, mbenes@suse.com Cc: linux-kernel@vger.kernel.org, peterz@infradead.org Subject: [PATCH v3 13/16] objtool: Keep track of retpoline call sites References: <20210326151159.128534163@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Provide infrastructure for architectures to rewrite/augment compiler generated retpoline calls. Similar to what we do for static_call()s, keep track of the instructions that are retpoline calls. Use the same list_head, since a retpoline call cannot also be a static_call. Signed-off-by: Peter Zijlstra (Intel) --- tools/objtool/check.c | 34 +++++++++++++++++++++++++++----- tools/objtool/include/objtool/arch.h | 2 + tools/objtool/include/objtool/check.h | 2 - tools/objtool/include/objtool/objtool.h | 1 tools/objtool/objtool.c | 1 5 files changed, 34 insertions(+), 6 deletions(-) --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -451,7 +451,7 @@ static int create_static_call_sections(s return 0; idx = 0; - list_for_each_entry(insn, &file->static_call_list, static_call_node) + list_for_each_entry(insn, &file->static_call_list, call_node) idx++; sec = elf_create_section(file->elf, ".static_call_sites", SHF_WRITE, @@ -460,7 +460,7 @@ static int create_static_call_sections(s return -1; idx = 0; - list_for_each_entry(insn, &file->static_call_list, static_call_node) { + list_for_each_entry(insn, &file->static_call_list, call_node) { site = (struct static_call_site *)sec->data->d_buf + idx; memset(site, 0, sizeof(struct static_call_site)); @@ -829,13 +829,16 @@ static int add_jump_destinations(struct else insn->type = INSN_JUMP_DYNAMIC_CONDITIONAL; + list_add_tail(&insn->call_node, + &file->retpoline_call_list); + insn->retpoline_safe = true; continue; } else if (insn->func) { /* internal or external sibling call (with reloc) */ insn->call_dest = reloc->sym; if (insn->call_dest->static_call_tramp) { - list_add_tail(&insn->static_call_node, + list_add_tail(&insn->call_node, &file->static_call_list); } continue; @@ -897,7 +900,7 @@ static int add_jump_destinations(struct /* internal sibling call (without reloc) */ insn->call_dest = insn->jump_dest->func; if (insn->call_dest->static_call_tramp) { - list_add_tail(&insn->static_call_node, + list_add_tail(&insn->call_node, &file->static_call_list); } } @@ -981,6 +984,9 @@ static int add_call_destinations(struct insn->type = INSN_CALL_DYNAMIC; insn->retpoline_safe = true; + list_add_tail(&insn->call_node, + &file->retpoline_call_list); + remove_insn_ops(insn); continue; @@ -988,7 +994,7 @@ static int add_call_destinations(struct insn->call_dest = reloc->sym; if (insn->call_dest && insn->call_dest->static_call_tramp) { - list_add_tail(&insn->static_call_node, + list_add_tail(&insn->call_node, &file->static_call_list); } @@ -1714,6 +1720,11 @@ static void mark_rodata(struct objtool_f file->rodata = found; } +__weak int arch_rewrite_retpolines(struct objtool_file *file) +{ + return 0; +} + static int decode_sections(struct objtool_file *file) { int ret; @@ -1742,6 +1753,10 @@ static int decode_sections(struct objtoo if (ret) return ret; + /* + * Must be before add_special_section_alts() as that depends on + * jump_dest being set. + */ ret = add_jump_destinations(file); if (ret) return ret; @@ -1778,6 +1793,15 @@ static int decode_sections(struct objtoo if (ret) return ret; + /* + * Must be after add_special_section_alts(), since this will emit + * alternatives. Must be after add_{jump,call}_destination(), since + * those create the call insn lists. + */ + ret = arch_rewrite_retpolines(file); + if (ret) + return ret; + return 0; } --- a/tools/objtool/include/objtool/arch.h +++ b/tools/objtool/include/objtool/arch.h @@ -87,4 +87,6 @@ int arch_decode_hint_reg(struct instruct bool arch_is_retpoline(struct symbol *sym); +int arch_rewrite_retpolines(struct objtool_file *file); + #endif /* _ARCH_H */ --- a/tools/objtool/include/objtool/check.h +++ b/tools/objtool/include/objtool/check.h @@ -39,7 +39,7 @@ struct alt_group { struct instruction { struct list_head list; struct hlist_node hash; - struct list_head static_call_node; + struct list_head call_node; struct list_head mcount_loc_node; struct section *sec; unsigned long offset; --- a/tools/objtool/include/objtool/objtool.h +++ b/tools/objtool/include/objtool/objtool.h @@ -18,6 +18,7 @@ struct objtool_file { struct elf *elf; struct list_head insn_list; DECLARE_HASHTABLE(insn_hash, 20); + struct list_head retpoline_call_list; struct list_head static_call_list; struct list_head mcount_loc_list; bool ignore_unreachables, c_file, hints, rodata; --- a/tools/objtool/objtool.c +++ b/tools/objtool/objtool.c @@ -125,6 +125,7 @@ struct objtool_file *objtool_open_read(c INIT_LIST_HEAD(&file.insn_list); hash_init(file.insn_hash); + INIT_LIST_HEAD(&file.retpoline_call_list); INIT_LIST_HEAD(&file.static_call_list); INIT_LIST_HEAD(&file.mcount_loc_list); file.c_file = !vmlinux && find_section_by_name(file.elf, ".comment");