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 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 960EAC4743C for ; Mon, 21 Jun 2021 12:03:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 76D8B6128E for ; Mon, 21 Jun 2021 12:03:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230272AbhFUMGF (ORCPT ); Mon, 21 Jun 2021 08:06:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229887AbhFUMGA (ORCPT ); Mon, 21 Jun 2021 08:06:00 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A28AC061760 for ; Mon, 21 Jun 2021 05:03:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=eJiAzP30aADyzX71NczWiAy4jG/zjICZ+p7+/n1+rRM=; b=QAH3ayxuScdewNS8gFvU7F4vhE v4u/ErYaEn09Y+yREG8iWW/8KjS7ARqinQvoMn3OA/isDZoCTbstPauzkF5CZP6B6BbBryokpUcZr CfnOsmvb6cj2UwXVxeH3SCQpfcTaTdxK1H2MSKYHtgCE0OLYC1CNNcP0khRrrTvE6qwR/85D8YrFc U0N1asJNBEluzfjr5XjzLebTy7hvhdZa01kudLEayMYvQTw4ZeIQq7QFjSoIBaDVwjm4xMxT2qHhp w+JeM2smgSP1lNpVruDV5TOlBoh0SBAjWersEaaZfQ66FUZ1wcpwrH+ywJUgTSdouSDbxZEDspPrM 88eMOcPw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1lvIdV-00D3hv-Fp; Mon, 21 Jun 2021 12:02:45 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id A62B0300597; Mon, 21 Jun 2021 14:02:39 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 01A50235EE380; Mon, 21 Jun 2021 14:02:38 +0200 (CEST) Message-ID: <20210621120120.784404944@infradead.org> User-Agent: quilt/0.66 Date: Mon, 21 Jun 2021 13:12:38 +0200 From: Peter Zijlstra To: jpoimboe@redhat.com, tglx@linutronix.de Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, joro@8bytes.org, boris.ostrovsky@oracle.com, jgross@suse.com, x86@kernel.org, mbenes@suse.com Subject: [PATCH 05/18] locking/lockdep: Improve noinstr vs errors References: <20210621111233.344964031@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 Better handle the failure paths. vmlinux.o: warning: objtool: debug_locks_off()+0x23: call to console_verbose() leaves .noinstr.text section vmlinux.o: warning: objtool: debug_locks_off()+0x19: call to __kasan_check_write() leaves .noinstr.text section debug_locks_off+0x19/0x40: instrument_atomic_write at include/linux/instrumented.h:86 (inlined by) __debug_locks_off at include/linux/debug_locks.h:17 (inlined by) debug_locks_off at lib/debug_locks.c:41 Fixes: 6eebad1ad303 ("lockdep: __always_inline more for noinstr") Signed-off-by: Peter Zijlstra (Intel) --- diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h index 2915f56ad421..edb5c186b0b7 100644 --- a/include/linux/debug_locks.h +++ b/include/linux/debug_locks.h @@ -27,8 +27,10 @@ extern int debug_locks_off(void); int __ret = 0; \ \ if (!oops_in_progress && unlikely(c)) { \ + instrumentation_begin(); \ if (debug_locks_off() && !debug_locks_silent) \ WARN(1, "DEBUG_LOCKS_WARN_ON(%s)", #c); \ + instrumentation_end(); \ __ret = 1; \ } \ __ret; \ diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index cb8af6a3e154..6fc60d363d26 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -843,7 +843,7 @@ static int count_matching_names(struct lock_class *new_class) } /* used from NMI context -- must be lockless */ -static __always_inline struct lock_class * +static noinstr struct lock_class * look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass) { struct lockdep_subclass_key *key; @@ -851,12 +851,14 @@ look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass) struct lock_class *class; if (unlikely(subclass >= MAX_LOCKDEP_SUBCLASSES)) { + instrumentation_begin(); debug_locks_off(); printk(KERN_ERR "BUG: looking up invalid subclass: %u\n", subclass); printk(KERN_ERR "turning off the locking correctness validator.\n"); dump_stack(); + instrumentation_end(); return NULL; } diff --git a/lib/debug_locks.c b/lib/debug_locks.c index 06d3135bd184..a75ee30b77cb 100644 --- a/lib/debug_locks.c +++ b/lib/debug_locks.c @@ -36,7 +36,7 @@ EXPORT_SYMBOL_GPL(debug_locks_silent); /* * Generic 'turn off all lock debugging' function: */ -noinstr int debug_locks_off(void) +int debug_locks_off(void) { if (debug_locks && __debug_locks_off()) { if (!debug_locks_silent) {