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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74668C433EF for ; Tue, 9 Nov 2021 22:05:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 497CB61178 for ; Tue, 9 Nov 2021 22:05:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235597AbhKIWH7 (ORCPT ); Tue, 9 Nov 2021 17:07:59 -0500 Received: from mail.skyhub.de ([5.9.137.197]:59390 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229811AbhKIWH6 (ORCPT ); Tue, 9 Nov 2021 17:07:58 -0500 Received: from zn.tnic (p200300ec2f18aa00aec912b1b11fde1a.dip0.t-ipconnect.de [IPv6:2003:ec:2f18:aa00:aec9:12b1:b11f:de1a]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id BB68F1EC0399; Tue, 9 Nov 2021 23:05:10 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1636495510; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=Hs94rUgeZ2VvaoKiTf4Jbb/sMwdZcSbUHieuZ19TcqA=; b=fU2PxbWCidirYisZ6OjPd6JrMnrj1HtVgU+MeP0yTcnivfn+RE+Ijmn42EDMbA7ChaR9J7 hVD5lFRAigc4uF4/NT8hFRjmyS5XnOo+lPKqvlCvgcGcuGdS5ZoCvrssN0uNZ1BijRWnkr TX7zwKlwrh8Rmn8ve7yib/riWLiMhPU= Date: Tue, 9 Nov 2021 23:05:04 +0100 From: Borislav Petkov To: Tony Luck Cc: X86 ML , LKML Subject: Re: [PATCH v0 05/12] x86/mce: Allow instrumentation during task work queueing Message-ID: References: <20211104144035.20107-1-bp@alien8.de> <20211104144035.20107-6-bp@alien8.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20211104144035.20107-6-bp@alien8.de> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 04, 2021 at 03:40:28PM +0100, Borislav Petkov wrote: > From: Borislav Petkov > > Fixes > > vmlinux.o: warning: objtool: do_machine_check()+0xdb1: call to queue_task_work() leaves .noinstr.text section > > Signed-off-by: Borislav Petkov > --- > arch/x86/kernel/cpu/mce/core.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c > index c7181e8e2845..65a8be420aff 100644 > --- a/arch/x86/kernel/cpu/mce/core.c > +++ b/arch/x86/kernel/cpu/mce/core.c > @@ -1451,6 +1451,8 @@ noinstr void do_machine_check(struct pt_regs *regs) > if (worst != MCE_AR_SEVERITY && !kill_current_task) > goto out; > > + instrumentation_begin(); so it might be nice to have a comment with each sandwich to say why sh*t won't go sideways when instrumentation happens in the #MC at that point like this shuts things up, but really we don't want instrumentation here either, except blah note to self: will need to go through the whole set. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette