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=-13.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 82D97C4CEC4 for ; Wed, 18 Sep 2019 09:02:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 51ED0218AF for ; Wed, 18 Sep 2019 09:02:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568797368; bh=lwmhaKk2DoGcG7qzZtBauVEYaJWZpkGPIgrTEbpVuHQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=I77WAFaAVDTNnafTRAZlyHbkwW+1D7RQQlekjDQSo1GWyMQiibMq5DmFuTSvbIFp7 ciW6JEQjRMwUzdDf5NGN1/ycCyrhsNp9/RsXKsjqi30bD8RnONqnSO0YWDMiS6qm5X c9EBCidsKpN8XCKgks0kg+qGaVPB3RTchuDh7bRc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730808AbfIRJCr (ORCPT ); Wed, 18 Sep 2019 05:02:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:46938 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725909AbfIRJCr (ORCPT ); Wed, 18 Sep 2019 05:02:47 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7842820640; Wed, 18 Sep 2019 09:02:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568797366; bh=lwmhaKk2DoGcG7qzZtBauVEYaJWZpkGPIgrTEbpVuHQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=2YY6sB07c+zPpM3Ky3Ceb7ZrPsrPh6bkuh5bowYMqToN8uhTjr/3QNmPYvYtIS57O fRtbK2HpOaY/qgA5TFGRP5mokdfIaJ3jJJr29UIbtWcGjURXb4gkKfofYo5gtPZTO8 U5ssMpNg7yE2zY4VNZvOgun7tkA9t3Ep9oLe9GB4= Date: Wed, 18 Sep 2019 10:02:41 +0100 From: Will Deacon To: Nathan Chancellor Cc: Arnd Bergmann , Catalin Marinas , Nick Desaulniers , Andrew Murray , Thomas Gleixner , "Peter Zijlstra (Intel)" , Mark Rutland , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com Subject: Re: [PATCH] [v2] arm64: fix unreachable code issue with cmpxchg Message-ID: <20190918090240.5cc3rfcuenefisgr@willie-the-truck> References: <20190910115643.391995-1-arnd@arndb.de> <20190917203425.GA31423@archlinux-threadripper> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190917203425.GA31423@archlinux-threadripper> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 17, 2019 at 01:34:25PM -0700, Nathan Chancellor wrote: > On Tue, Sep 10, 2019 at 01:56:22PM +0200, Arnd Bergmann wrote: > > On arm64 build with clang, sometimes the __cmpxchg_mb is not inlined > > when CONFIG_OPTIMIZE_INLINING is set. > > Clang then fails a compile-time assertion, because it cannot tell at > > compile time what the size of the argument is: > > > > mm/memcontrol.o: In function `__cmpxchg_mb': > > memcontrol.c:(.text+0x1a4c): undefined reference to `__compiletime_assert_175' > > memcontrol.c:(.text+0x1a4c): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `__compiletime_assert_175' > > > > Mark all of the cmpxchg() style functions as __always_inline to > > ensure that the compiler can see the result. > > > > Acked-by: Nick Desaulniers > > Reported-by: Nathan Chancellor > > Link: https://github.com/ClangBuiltLinux/linux/issues/648 > > Reviewed-by: Nathan Chancellor > > Tested-by: Nathan Chancellor > > Reviewed-by: Andrew Murray > > Tested-by: Andrew Murray > > Signed-off-by: Arnd Bergmann > > --- > > v2: skip unneeded changes, as suggested by Andrew Murray > > --- > > arch/arm64/include/asm/cmpxchg.h | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/arch/arm64/include/asm/cmpxchg.h b/arch/arm64/include/asm/cmpxchg.h > > index a1398f2f9994..f9bef42c1411 100644 > > --- a/arch/arm64/include/asm/cmpxchg.h > > +++ b/arch/arm64/include/asm/cmpxchg.h > > @@ -62,7 +62,7 @@ __XCHG_CASE( , , mb_, 64, dmb ish, nop, , a, l, "memory") > > #undef __XCHG_CASE > > > > #define __XCHG_GEN(sfx) \ > > -static inline unsigned long __xchg##sfx(unsigned long x, \ > > +static __always_inline unsigned long __xchg##sfx(unsigned long x, \ > > volatile void *ptr, \ > > int size) \ > > { \ > > @@ -148,7 +148,7 @@ __CMPXCHG_DBL(_mb) > > #undef __CMPXCHG_DBL > > > > #define __CMPXCHG_GEN(sfx) \ > > -static inline unsigned long __cmpxchg##sfx(volatile void *ptr, \ > > +static __always_inline unsigned long __cmpxchg##sfx(volatile void *ptr, \ > > unsigned long old, \ > > unsigned long new, \ > > int size) \ > > @@ -255,7 +255,7 @@ __CMPWAIT_CASE( , , 64); > > #undef __CMPWAIT_CASE > > > > #define __CMPWAIT_GEN(sfx) \ > > -static inline void __cmpwait##sfx(volatile void *ptr, \ > > +static __always_inline void __cmpwait##sfx(volatile void *ptr, \ > > unsigned long val, \ > > int size) \ > > { \ > > -- > > 2.20.0 > > > > Looks like the arm64 pull request happened without this patch so clang > all{mod,yes}config builds are broken. Did the maintainers have any > further comments on it or could this make it in with the next one? Fear not! I plan to send this with some other fixes we've got for -rc1. I just to get my CI scripts going again (new machine), but that shouldn't take long. Will