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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 5000EC2D0E4 for ; Thu, 19 Nov 2020 12:02:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C86F3246D3 for ; Thu, 19 Nov 2020 12:02:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="lZa8DC8a" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726949AbgKSMBc (ORCPT ); Thu, 19 Nov 2020 07:01:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726843AbgKSMBa (ORCPT ); Thu, 19 Nov 2020 07:01:30 -0500 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D797C0613CF for ; Thu, 19 Nov 2020 04:01:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=knLBXYswT782Ey+RcblRs+pvakWtzlF6q8jukITwxYA=; b=lZa8DC8aEzVUsMSyHoKW2JbolL pJQnHS0Ue3hDsOm2FmImsl1hJSgW6Q8esiEE8aRs+WeTdlm5OajXi/fpp2ZgHT3XvmOqCFKyy0C9R 07RzhW5crnq0hLH0LpU6/y1tDALnsi6/YHMu4gl0+SEXK1ArdaLpho+BtL71ujie4k5IG9qFeZBxy 5XAW+V8Qw6o/jbJ0Vibg+QYbN4W6bsbaKifNDXQ5TaGCowMPHAbn1Fhg5wsfABVGEPwECNsCiq88G /jJHoyjCQ6K0k5moUEh9SogDfKhpoXt/UDlvZxvNUJkUX6EgHzFU7ZQDDr8HFu51z1KbZmyZVcfS6 e+ofUWnw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kficu-0001pE-9C; Thu, 19 Nov 2020 12:01:24 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id D788C301E02; Thu, 19 Nov 2020 13:01:22 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id AE8082C15A620; Thu, 19 Nov 2020 13:01:22 +0100 (CET) Date: Thu, 19 Nov 2020 13:01:22 +0100 From: Peter Zijlstra To: Shinichiro Kawasaki Cc: =?iso-8859-1?Q?J=FCrgen_Gro=DF?= , Andy Lutomirski , Andrew Cooper , Josh Poimboeuf , "linux-kernel@vger.kernel.org" , Nicholas Piggin , Damien Le Moal , X86 ML Subject: Re: WARNING: can't access registers at asm_common_interrupt Message-ID: <20201119120122.GJ3121392@hirez.programming.kicks-ass.net> References: <20201111195900.2x7kfce2ejkmrzi3@treble> <20201111200730.GM2628@hirez.programming.kicks-ass.net> <20201111201506.bftpmx4svxn376tn@treble> <61b2538f-7be6-8f4a-9395-03071b5cc6f0@citrix.com> <20201116130413.GC3121392@hirez.programming.kicks-ass.net> <20201118082254.GH3121378@hirez.programming.kicks-ass.net> <20201119115059.dns4hvull3l3dwx3@shindev.dhcp.fujisawa.hgst.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201119115059.dns4hvull3l3dwx3@shindev.dhcp.fujisawa.hgst.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 19, 2020 at 11:51:00AM +0000, Shinichiro Kawasaki wrote: > I tried Peter's patch in my test system and result looks good. The warning is > still observed with 5.10-rc4. With the patch on top of 5.10-rc4, the warning > disappeared. The patch on its own is not sufficient to fix things; there needs to be an accompanying objtool patch to generate the correct unwind information. This patch only ensures objtool has enough information to be able to dtrt, but as it stands it shouldn't even compile, it should complain about an alternative trying to modify the stack and bail.