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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F728C83F12 for ; Mon, 28 Aug 2023 17:47:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232875AbjH1RrH (ORCPT ); Mon, 28 Aug 2023 13:47:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48752 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231164AbjH1Rqg (ORCPT ); Mon, 28 Aug 2023 13:46:36 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E47DEE for ; Mon, 28 Aug 2023 10:46:34 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CC04763D0A for ; Mon, 28 Aug 2023 17:46:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A47BCC433CC; Mon, 28 Aug 2023 17:46:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1693244793; bh=rqIgUEJ2gFNDPW2upRgvZqXnuhfLL6A/8Oy8KbEhK4Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=b6pMM8AP7WAcW0DNuOjVIwOpbQKp0udmz2MPGL4OU24kjJSoblFbwTFvc9NL3kPF6 vuEp7gsbBr02Aw1u3QfqhUP1MwmxHH5dAMy2i0BbwQJT8nmUy0KPys/Ss9fs9hXzMI HhkFpPLQ+N+memByUvgZa2aABT7+wtS/orJw+8nhT4eQi8pTC4YRkKBE2FE/gjumKD LpiHqqOaBuLFA7ESXjZT/RQ758nOSoQuogWyFr72yb4BSgibQVPGcJ3huO4YACaU7I pxLZnhYsDu40Baj+ilZaJ17edxzq08FoRbHflsv4Yqru4lMbEiST/PGMgvXwmtKN5q g+5DkhOy8+dNQ== Date: Mon, 28 Aug 2023 10:46:31 -0700 From: Nathan Chancellor To: ndesaulniers@google.com Cc: Michael Ellerman , Nicholas Piggin , Christophe Leroy , Tom Rix , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, kernel test robot Subject: Re: [PATCH] Revert "Revert "powerpc/xmon: Relax frame size for clang"" Message-ID: <20230828174631.GA1255864@dev-arch.thelio-3990X> References: <20230828-ppc_rerevert-v1-1-74f55b818907@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230828-ppc_rerevert-v1-1-74f55b818907@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 28, 2023 at 10:35:26AM -0700, ndesaulniers@google.com wrote: > This reverts commit 7f3c5d099b6f8452dc4dcfe4179ea48e6a13d0eb. > > Turns out that this is reproducible still under specific compiler > versions (mea culpa: I did not test every supported version of clang), > and even a few randconfigs bots found. > > We'll have to revisit this again in the future, for now back this out. > > Reported-by: Nathan Chancellor > Closes: https://github.com/ClangBuiltLinux/linux/issues/252#issuecomment-1690371256 > Reported-by: kernel test robot > Closes: https://lore.kernel.org/llvm/202308260344.Vc4Giuk7-lkp@intel.com/ > Signed-off-by: Nick Desaulniers I know this is just a straight reapplication of the original workaround but could we use ccflags here instead of KBUILD_CFLAGS (with it placed after the NO_MIMINAL_TOC assignment)? # clang stores addresses on the stack causing the frame size to blow # out. See https://github.com/ClangBuiltLinux/linux/issues/252 ccflags-$(CONFIG_CC_IS_CLANG) += -Wframe-larger-than=4096 The addition to KBUILD_CFLAGS makes me think this flags will get applied to the rest of the kernel but I have not actually verified. Regardless: Reviewed-by: Nathan Chancellor Side note, seems like b4 is still doing the thing with "From:". > --- > arch/powerpc/xmon/Makefile | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile > index 7705aa74a24d..d334de392e6c 100644 > --- a/arch/powerpc/xmon/Makefile > +++ b/arch/powerpc/xmon/Makefile > @@ -10,6 +10,12 @@ KCSAN_SANITIZE := n > # Disable ftrace for the entire directory > ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE) > > +ifdef CONFIG_CC_IS_CLANG > +# clang stores addresses on the stack causing the frame size to blow > +# out. See https://github.com/ClangBuiltLinux/linux/issues/252 > +KBUILD_CFLAGS += -Wframe-larger-than=4096 > +endif > + > ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC) > > obj-y += xmon.o nonstdio.o spr_access.o xmon_bpts.o > > --- > base-commit: 2ee82481c392eec06a7ef28df61b7f0d8e45be2e > change-id: 20230828-ppc_rerevert-647427f04ce1 > > Best regards, > -- > Nick Desaulniers >