From patchwork Wed Jun 15 15:41:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 12882592 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC450CCA47E for ; Wed, 15 Jun 2022 15:42:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244297AbiFOPmE (ORCPT ); Wed, 15 Jun 2022 11:42:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245562AbiFOPmA (ORCPT ); Wed, 15 Jun 2022 11:42:00 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 19B0B340D1; Wed, 15 Jun 2022 08:41:59 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id EE639CE2138; Wed, 15 Jun 2022 15:41:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1B96C3411E; Wed, 15 Jun 2022 15:41:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1655307715; bh=4Ia3elHBO5wV1Wtcnws73syokEmGauhOYfmERPv6i94=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HnPMBmk74FNf2DpfJ01S12iNBDG8lC41iLKJi4HvksDvwrX5OnzaCeAoN/uTk2Pku pI9/bSoOGHAhDk5pUkbzueky4wL8niKWInlpTkSZSjhxrwsbKD4oTve21nYYY9XBZV ppz/iZHu3nu/ivPwJkMeEYsUexj6yinBYLlwiFKPB5CKcB/yS/yGl9vp48FM14QuOu 6RM01gEp5TS/O5I/QF7UcnXw/HJTk6JQCCW6EW+u+oiMxNMpA9rTTNCyO6RtZ437FC ChtySs9q7P3JWnGjrBzLEdD4Y4IM1LOGMWEf1H0sSsH/Z/4JXs5sLYZFViDKCSyXHn P7W8VqCOYoVmg== From: Ard Biesheuvel To: linux-kernel@vger.kernel.org Cc: Ard Biesheuvel , Peter Zijlstra , Mark Rutland , Thomas Bogendoerfer , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , linux-mips@vger.kernel.org, linux-s390@vger.kernel.org Subject: [PATCH v2 2/3] jump_label: mips: move module NOP patching into arch code Date: Wed, 15 Jun 2022 17:41:41 +0200 Message-Id: <20220615154142.1574619-3-ardb@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220615154142.1574619-1-ardb@kernel.org> References: <20220615154142.1574619-1-ardb@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=6479; h=from:subject; bh=4Ia3elHBO5wV1Wtcnws73syokEmGauhOYfmERPv6i94=; b=owEB7QES/pANAwAKAcNPIjmS2Y8kAcsmYgBiqf2zymD1Cf8od4ETwiJboEwkDwSQnewfdrwcZAaN a/ipfFWJAbMEAAEKAB0WIQT72WJ8QGnJQhU3VynDTyI5ktmPJAUCYqn9swAKCRDDTyI5ktmPJB31C/ 48zm1zpCvIIRZLQCqT+OIgGYRBNGgnWHfte62MrMyQi6VL0DfvfStNVnRWtSj9T2Nt2r6DvQfM3q/g lAC4mCRzUIz6VaClY4d1TXL6Ir0rgajHzuQNNy+Z75vms7BJhofrpMInzPWZKvpgaTQlPq6Reld5Di Opr4ZmFkadMwRtQGLVOwZNNcWNN79e3OaSUIZh1wCFKBj69+FygmmnLYzLH0q8bmu9sZsCV7rAh/F9 A3cYKixruvV514BUm/ZZV6wfZbfuAPMSj6RR4eM8Dle5AnQcJ7wuEIDzB/xZT8CV7TtlDmtyuxGSkL qWC4NgYxbX3WXTqigm80s5hPiB1djb/IdBlx25nRaNZ48C0nHYEOw228v3bqokwWs9jNazhel9qcOR O6a2xVHqvPn7BLKM+FJP6twsWu6wcLU7BXa7jwrv6prXk30aR9OkSlFGRcaL3m5OYXxpuAVWov4qn0 Og7PtGxqfkVlizIJG7h9nJ0yYXRbZbcbvd+KbcheQG/J8= X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org MIPS is the only remaining architecture that needs to patch jump label NOP encodings to initialize them at load time. So let's move the module patching part of that from generic code into arch/mips, and drop it from the others. Signed-off-by: Ard Biesheuvel Acked-by: Alexander Gordeev --- arch/mips/kernel/jump_label.c | 19 ++++++++++++++ arch/mips/kernel/module.c | 5 ++-- arch/s390/kernel/module.c | 1 - arch/sparc/kernel/module.c | 3 --- arch/x86/kernel/module.c | 3 --- include/linux/jump_label.h | 7 +---- kernel/jump_label.c | 27 +------------------- 7 files changed, 24 insertions(+), 41 deletions(-) diff --git a/arch/mips/kernel/jump_label.c b/arch/mips/kernel/jump_label.c index 662c8db9f45b..e4c775e7c063 100644 --- a/arch/mips/kernel/jump_label.c +++ b/arch/mips/kernel/jump_label.c @@ -88,3 +88,22 @@ void arch_jump_label_transform(struct jump_entry *e, mutex_unlock(&text_mutex); } + +#ifdef CONFIG_MODULE +void jump_label_apply_nops(struct module *mod) +{ + struct jump_entry *iter_start = mod->jump_entries; + struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; + struct jump_entry *iter; + + /* if the module doesn't have jump label entries, just return */ + if (iter_start == iter_stop) + return; + + for (iter = iter_start; iter < iter_stop; iter++) { + /* Only write NOPs for arch_branch_static(). */ + if (jump_label_init_type(iter) == JUMP_LABEL_NOP) + arch_jump_label_transform(iter, JUMP_LABEL_NOP); + } +} +#endif diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index 14f46d17500a..0c936cbf20c5 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -21,6 +21,7 @@ #include #include +extern void jump_label_apply_nops(struct module *mod); struct mips_hi16 { struct mips_hi16 *next; @@ -428,8 +429,8 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *s; char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; - /* Make jump label nops. */ - jump_label_apply_nops(me); + if (IS_ENABLED(CONFIG_JUMP_LABEL)) + jump_label_apply_nops(me); INIT_LIST_HEAD(&me->arch.dbe_list); for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c index 26125a9c436d..2d159b32885b 100644 --- a/arch/s390/kernel/module.c +++ b/arch/s390/kernel/module.c @@ -548,6 +548,5 @@ int module_finalize(const Elf_Ehdr *hdr, #endif /* CONFIG_FUNCTION_TRACER */ } - jump_label_apply_nops(me); return 0; } diff --git a/arch/sparc/kernel/module.c b/arch/sparc/kernel/module.c index df39580f398d..66c45a2764bc 100644 --- a/arch/sparc/kernel/module.c +++ b/arch/sparc/kernel/module.c @@ -208,9 +208,6 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, struct module *me) { - /* make jump label nops */ - jump_label_apply_nops(me); - do_patch_sections(hdr, sechdrs); /* Cheetah's I-cache is fully coherent. */ diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c index b98ffcf4d250..95b9cf25d4bd 100644 --- a/arch/x86/kernel/module.c +++ b/arch/x86/kernel/module.c @@ -304,9 +304,6 @@ int module_finalize(const Elf_Ehdr *hdr, tseg, tseg + text->sh_size); } - /* make jump label nops */ - jump_label_apply_nops(me); - if (orc && orc_ip) unwind_module_init(me, (void *)orc_ip->sh_addr, orc_ip->sh_size, (void *)orc->sh_addr, orc->sh_size); diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index bf1eef337a07..2003a0935478 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -230,12 +230,12 @@ extern void static_key_slow_inc(struct static_key *key); extern void static_key_slow_dec(struct static_key *key); extern void static_key_slow_inc_cpuslocked(struct static_key *key); extern void static_key_slow_dec_cpuslocked(struct static_key *key); -extern void jump_label_apply_nops(struct module *mod); extern int static_key_count(struct static_key *key); extern void static_key_enable(struct static_key *key); extern void static_key_disable(struct static_key *key); extern void static_key_enable_cpuslocked(struct static_key *key); extern void static_key_disable_cpuslocked(struct static_key *key); +extern enum jump_label_type jump_label_init_type(struct jump_entry *entry); /* * We should be using ATOMIC_INIT() for initializing .enabled, but @@ -303,11 +303,6 @@ static inline int jump_label_text_reserved(void *start, void *end) static inline void jump_label_lock(void) {} static inline void jump_label_unlock(void) {} -static inline int jump_label_apply_nops(struct module *mod) -{ - return 0; -} - static inline void static_key_enable(struct static_key *key) { STATIC_KEY_CHECK_USE(key); diff --git a/kernel/jump_label.c b/kernel/jump_label.c index b156e152d6b4..b1ac2948be79 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -508,7 +508,7 @@ void __init jump_label_init(void) #ifdef CONFIG_MODULES -static enum jump_label_type jump_label_init_type(struct jump_entry *entry) +enum jump_label_type jump_label_init_type(struct jump_entry *entry) { struct static_key *key = jump_entry_key(entry); bool type = static_key_type(key); @@ -596,31 +596,6 @@ static void __jump_label_mod_update(struct static_key *key) } } -/*** - * apply_jump_label_nops - patch module jump labels with arch_get_jump_label_nop() - * @mod: module to patch - * - * Allow for run-time selection of the optimal nops. Before the module - * loads patch these with arch_get_jump_label_nop(), which is specified by - * the arch specific jump label code. - */ -void jump_label_apply_nops(struct module *mod) -{ - struct jump_entry *iter_start = mod->jump_entries; - struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; - struct jump_entry *iter; - - /* if the module doesn't have jump label entries, just return */ - if (iter_start == iter_stop) - return; - - for (iter = iter_start; iter < iter_stop; iter++) { - /* Only write NOPs for arch_branch_static(). */ - if (jump_label_init_type(iter) == JUMP_LABEL_NOP) - arch_jump_label_transform_static(iter, JUMP_LABEL_NOP); - } -} - static int jump_label_add_module(struct module *mod) { struct jump_entry *iter_start = mod->jump_entries;