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 8A927C433EF for ; Sun, 28 Nov 2021 13:10:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352694AbhK1NOO (ORCPT ); Sun, 28 Nov 2021 08:14:14 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:42024 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357395AbhK1NMM (ORCPT ); Sun, 28 Nov 2021 08:12:12 -0500 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 dfw.source.kernel.org (Postfix) with ESMTPS id CCA7460FE4; Sun, 28 Nov 2021 13:08:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AAB6EC004E1; Sun, 28 Nov 2021 13:08:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638104936; bh=dl2l8+X50Xzu8JdiY/48cXxuGVId4I8bEAKwJt0nmCo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hXcSo+eAlaHYwRQ53QRiheDZCvgAsUG4a6S8uVhB6mxK0FdIZjGzV96+y7dUazP1M mGEuV0eMtJ5KrM8AyEqUjO7BGliIZl0+UC8EFJ6rlH0IfjYJcg42oKDqIjYUVOWCTU izhKTxz1OgvN0ZXHHpO5HHTKBLmJbP4FxsLlYVeg= Date: Sun, 28 Nov 2021 14:08:53 +0100 From: Greg Kroah-Hartman To: Salvatore Bonaccorso Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, "Peter Zijlstra (Intel)" , Sasha Levin Subject: Re: [PATCH 4.19 088/323] locking/lockdep: Avoid RCU-induced noinstr fail Message-ID: References: <20211124115718.822024889@linuxfoundation.org> <20211124115721.937655496@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 28, 2021 at 02:06:30PM +0100, Greg Kroah-Hartman wrote: > On Sun, Nov 28, 2021 at 01:11:11PM +0100, Salvatore Bonaccorso wrote: > > Hi, > > > > On Sun, Nov 28, 2021 at 12:59:24PM +0100, Salvatore Bonaccorso wrote: > > > Hi, > > > > > > On Sun, Nov 28, 2021 at 10:46:13AM +0100, Salvatore Bonaccorso wrote: > > > > Hi, > > > > > > > > On Wed, Nov 24, 2021 at 12:54:38PM +0100, Greg Kroah-Hartman wrote: > > > > > From: Peter Zijlstra > > > > > > > > > > [ Upstream commit ce0b9c805dd66d5e49fd53ec5415ae398f4c56e6 ] > > > > > > > > > > vmlinux.o: warning: objtool: look_up_lock_class()+0xc7: call to rcu_read_lock_any_held() leaves .noinstr.text section > > > > > > > > For 4.19.218 at least this commit seems to cause a build failure for > > > > cpupower, if warnings are treated as errors, I have not seen the same > > > > for the 5.10.80 build: > > > > > > > > gcc -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -DVERSION=\"4.19\" -DPACKAGE=\"cpupower\" -DPACKAGE_BUGREPORT=\"Debian\ \(reportbug\ linux-cpupower\)\" -D_GNU_SOURCE -pipe -DNLS -Wall -Wchar-subscripts -Wpointer-arith > > > > -Wsign-compare -Wno-pointer-sign -Wdeclaration-after-statement -Wshadow -Os -fomit-frame-pointer -fPIC -o /home/build/linux-4.19.218/debian/build/build-tools/tools/power/cpupower/lib/cpupower.o -c lib/cpupower.c > > > > In file included from lockdep.c:28: > > > > ../../../kernel/locking/lockdep.c: In function ‘look_up_lock_class’: > > > > ../../../kernel/locking/lockdep.c:694:2: error: implicit declaration of function ‘hlist_for_each_entry_rcu_notrace’; did you mean ‘hlist_for_each_entry_continue’? [-Werror=implicit-function-declaration] > > > > hlist_for_each_entry_rcu_notrace(class, hash_head, hash_entry) { > > > > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > hlist_for_each_entry_continue > > > > ../../../kernel/locking/lockdep.c:694:53: error: ‘hash_entry’ undeclared (first use in this function); did you mean ‘hash_ptr’? > > > > hlist_for_each_entry_rcu_notrace(class, hash_head, hash_entry) { > > > > ^~~~~~~~~~ > > > > hash_ptr > > > > ../../../kernel/locking/lockdep.c:694:53: note: each undeclared identifier is reported only once for each function it appears in > > > > ../../../kernel/locking/lockdep.c:694:64: error: expected ‘;’ before ‘{’ token > > > > hlist_for_each_entry_rcu_notrace(class, hash_head, hash_entry) { > > > > ^~ > > > > ; > > > > ../../../kernel/locking/lockdep.c:706:1: warning: control reaches end of non-void function [-Wreturn-type] > > > > } > > > > ^ > > > > cc1: some warnings being treated as errors > > > > make[5]: *** [/home/build/linux-4.19.218/tools/build/Makefile.build:97: /home/build/linux-4.19.218/debian/build/build-tools/tools/lib/lockdep/lockdep.o] Error 1 > > > > make[4]: *** [Makefile:121: /home/build/linux-4.19.218/debian/build/build-tools/tools/lib/lockdep/liblockdep-in.o] Error 2 > > > > make[4]: Leaving directory '/home/build/linux-4.19.218/tools/lib/lockdep' > > > > make[3]: *** [/home/build/linux-4.19.218/debian/rules.d/tools/lib/lockdep/Makefile:16: all] Error 2 > > > > make[3]: Leaving directory '/home/build/linux-4.19.218/debian/build/build-tools/tools/lib/lockdep' > > > > make[2]: *** [debian/rules.real:795: build-liblockdep] Error 2 > > > > make[2]: *** Waiting for unfinished jobs.... > > > > > > > > I was not yet able to look further on it. > > > > > > Might actually be a distro specific issue, needs some further > > > investigation. > > > > I'm really sorry about the doubled noice, so here is the stance. I can > > reproduce distro indpeendent, but the initial claim was wrong. It can > > be reproduced for 4.19.218: > > > > $ LC_ALL=C.UTF-8 V=1 ARCH=x86 make -C tools liblockdep > > make: Entering directory '/home/build/linux-stable/tools' > > mkdir -p lib/lockdep && make subdir=lib/lockdep -C lib/lockdep > > make[1]: Entering directory '/home/build/linux-stable/tools/lib/lockdep' > > make -f /home/build/linux-stable/tools/build/Makefile.build dir=. obj=fixdep > > gcc -Wp,-MD,./.fixdep.o.d -Wp,-MT,fixdep.o -D"BUILD_STR(s)=#s" -c -o fixdep.o fixdep.c > > ld -r -o fixdep-in.o fixdep.o > > gcc -o fixdep fixdep-in.o > > gcc -Wp,-MD,./.common.o.d -Wp,-MT,common.o -g -DCONFIG_LOCKDEP -DCONFIG_STACKTRACE -DCONFIG_PROVE_LOCKING -DBITS_PER_LONG=__WORDSIZE -DLIBLOCKDEP_VERSION='"4.19.218"' -rdynamic -O0 -g -fPIC -Wall -I. -I./uinclude -I./include -I../../include -D"BUILD_STR(s)=#s" -c -o common.o common.c > > gcc -Wp,-MD,./.lockdep.o.d -Wp,-MT,lockdep.o -g -DCONFIG_LOCKDEP -DCONFIG_STACKTRACE -DCONFIG_PROVE_LOCKING -DBITS_PER_LONG=__WORDSIZE -DLIBLOCKDEP_VERSION='"4.19.218"' -rdynamic -O0 -g -fPIC -Wall -I. -I./uinclude -I./include -I../../include -D"BUILD_STR(s)=#s" -c -o lockdep.o lockdep.c > > In file included from lockdep.c:28: > > ../../../kernel/locking/lockdep.c: In function ‘look_up_lock_class’: > > ../../../kernel/locking/lockdep.c:692:2: warning: implicit declaration of function ‘hlist_for_each_entry_rcu_notrace’; did you mean ‘hlist_for_each_entry_continue’? [-Wimplicit-function-declaration] > > hlist_for_each_entry_rcu_notrace(class, hash_head, hash_entry) { > > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > hlist_for_each_entry_continue > > ../../../kernel/locking/lockdep.c:692:53: error: ‘hash_entry’ undeclared (first use in this function); did you mean ‘hash_ptr’? > > hlist_for_each_entry_rcu_notrace(class, hash_head, hash_entry) { > > ^~~~~~~~~~ > > hash_ptr > > ../../../kernel/locking/lockdep.c:692:53: note: each undeclared identifier is reported only once for each function it appears in > > ../../../kernel/locking/lockdep.c:692:64: error: expected ‘;’ before ‘{’ token > > hlist_for_each_entry_rcu_notrace(class, hash_head, hash_entry) { > > ^~ > > ; > > ../../../kernel/locking/lockdep.c:704:1: warning: control reaches end of non-void function [-Wreturn-type] > > } > > ^ > > make[2]: *** [/home/build/linux-stable/tools/build/Makefile.build:97: lockdep.o] Error 1 > > make[1]: *** [Makefile:121: liblockdep-in.o] Error 2 > > make[1]: Leaving directory '/home/build/linux-stable/tools/lib/lockdep' > > make: *** [Makefile:66: liblockdep] Error 2 > > make: Leaving directory '/home/build/linux-stable/tools' > > > > Reverting upstream ce0b9c805dd6 ("locking/lockdep: Avoid RCU-induced > > noinstr fail") on top of 4.19.218 fixes the issue. > > > > So back to square one, and again apologies for the intermediate noise! > > What config/arch is causing this to break? And if you add rchlist.h to > the include files for lockdep.c, does that resolve the issue? I haven't > seen any other reports of this yet. Ah, it's the tools being built here, sorry, that was confusing. Yes, I can duplicate this, when building liblockdep. As that code just got ripped out of upstream, perhaps just use the out-of-tree code instead now? thanks, greg k-h