From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pegase2.c-s.fr (pegase2.c-s.fr [93.17.235.10]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 994D7204C31 for ; Tue, 25 Feb 2025 07:50:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=93.17.235.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740469805; cv=none; b=d8qSJI/wnaWnTQhtkpctGvChtfBrIjQRDSIl991llVBfQDwtXAkDlWfZctyqhTOZnqRUHljfmLDltfcgxQjtHwVjyX6RUnmDNBjwYw4TyVIAu3SoxYiw9dcdsFbR8jBiW4GVqwzdwkM5kZ8e0fcTprX3T2qvrEwlZINzuwg/BOw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740469805; c=relaxed/simple; bh=09ibOkxEH89zpgu/YOvZXAOdkjAqyD57M71vN9DlDIs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=XaLm0UWPGBagvDyPdcgogLw0iGYN24KxJLbX+cD9OE+SB2yjYQTlKO4mEGJJavuTE9d8s6Se7heidc248VKjk1cDCKWJ+gTreJgcRjBWc183AKc0AdGThImWXRa20Q33MIBxUaQCywTOOXIqAiwfMtRgHQ0IZDt8lf/XtQZBf+g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=csgroup.eu; spf=pass smtp.mailfrom=csgroup.eu; arc=none smtp.client-ip=93.17.235.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=csgroup.eu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=csgroup.eu Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4Z28XW5p6Cz9sSH; Tue, 25 Feb 2025 08:35:39 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id LNoX8tsTPzIV; Tue, 25 Feb 2025 08:35:39 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4Z28XW50Xsz9sS8; Tue, 25 Feb 2025 08:35:39 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 98D598B780; Tue, 25 Feb 2025 08:35:39 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id D597ggcl3448; Tue, 25 Feb 2025 08:35:39 +0100 (CET) Received: from [192.168.235.99] (unknown [192.168.235.99]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 283828B77C; Tue, 25 Feb 2025 08:35:39 +0100 (CET) Message-ID: <7d23db63-6909-48e2-8262-fb000aa714a5@csgroup.eu> Date: Tue, 25 Feb 2025 08:35:38 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH] objtool: Skip unannotated intra-function call warning for bl+mflr pattern To: Nathan Chancellor Cc: Sathvika Vasireddy , jpoimboe@kernel.org, peterz@infradead.org, npiggin@gmail.com, maddy@linux.ibm.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, llvm@lists.linux.dev References: <20250219162014.10334-1-sv@linux.ibm.com> <3223ec0e-c445-4bbf-ae72-276688e40908@csgroup.eu> <8f4ec6d4-2646-4a87-b3a1-edfaecff2a01@csgroup.eu> <20250224170922.GA585841@ax162> Content-Language: fr-FR From: Christophe Leroy In-Reply-To: <20250224170922.GA585841@ax162> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Le 24/02/2025 à 18:09, Nathan Chancellor a écrit : > On Mon, Feb 24, 2025 at 02:19:14PM +0100, Christophe Leroy wrote: >> Well, this problem already exists on clang 18 it seems: >> >> 00000004 : >> 4: 7c 08 02 a6 mflr r0 >> 8: 94 21 ff e0 stwu r1,-32(r1) >> c: 93 c1 00 18 stw r30,24(r1) >> 10: 90 01 00 24 stw r0,36(r1) >> 14: 93 a1 00 14 stw r29,20(r1) >> 18: 48 00 00 05 bl 1c >> 1c: 38 a0 00 00 li r5,0 >> 20: 7f c8 02 a6 mflr r30 >> >> While GCC generates: >> >> 00000418 : >> 418: 94 21 ff e0 stwu r1,-32(r1) >> 41c: 7c 08 02 a6 mflr r0 >> 420: 42 9f 00 05 bcl 20,4*cr7+so,424 >> 424: 39 20 00 00 li r9,0 >> 428: 93 c1 00 18 stw r30,24(r1) >> 42c: 7f c8 02 a6 mflr r30 >> >> So lets make the kernel tolerate it allthough it should be fixed on clang at >> the end. >> >> I can't find any related issue in the clang issues database >> (https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fllvm%2Fllvm-project%2Fissues&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C3c10d37fecd94c692acb08dd54f5ff51%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638760137702082512%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=qOjbONjWUuXFKUNb42yEPXgXmvU6x%2BuwbGSg2Ep6WRk%3D&reserved=0), should we open one ? > > Yes please, especially if you happen to have a simplified reproducer > (but no worries if not). I can make sure it gets labeled for the PowerPC > backend folks to take a look at. > Done, see https://github.com/llvm/llvm-project/issues/128644