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 694AFC433EF for ; Sat, 7 May 2022 14:00:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1446380AbiEGODr (ORCPT ); Sat, 7 May 2022 10:03:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44650 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231375AbiEGODq (ORCPT ); Sat, 7 May 2022 10:03:46 -0400 Received: from mout02.posteo.de (mout02.posteo.de [185.67.36.66]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6CA1B29CB9 for ; Sat, 7 May 2022 06:59:59 -0700 (PDT) Received: from submission (posteo.de [185.67.36.169]) by mout02.posteo.de (Postfix) with ESMTPS id 741BE24010B for ; Sat, 7 May 2022 15:59:57 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.de; s=2017; t=1651931997; bh=yFqvCYHZne7q/UPkBtj7W4yKjBgYImmwkLi8nvU5Z5U=; h=From:To:Cc:Subject:Date:From; b=D7mK36YkHmpaLc+7LyPZ4S5wHFPUqY/+HUr15oIe01JuflO2i09e05dT1TKparHgj 0eB6756XKxMKNBl2gCFOLQd+gN0laa5yyA+KkHuOxVE+gXv6rWCKSl9sH2l/6LJ7Nq 8WBeViM7IwOUKF2b9EMBR/1Nw+WO1V0U11mMvFvU+nUmybDdy8dX0U8ajnY52tlheW ZszNGsGg2rs/D3qZPc1HcTUW04voWtBJmr7ZT/o8Q8YebD4pUvBixQhfBqL+8uDkJM J+F62DC0MhuADIm5+dUwi1ZPKb4IUcoWDlS02b/pQyii1zqK34E/5co+cKcYC84KOG EuqPdiTfZB7pA== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4KwTZz2wkSz9rxP; Sat, 7 May 2022 15:59:55 +0200 (CEST) From: Manuel Ullmann To: Thorsten Leemhuis Cc: Manuel Ullmann , Igor Russkikh , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, regressions@lists.linux.dev, davem@davemloft.net, ndanilov@marvell.com, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, Jordan Leppert , Holger =?utf-8?Q?Hoffst=C3=A4tte?= , koo5 Subject: Re: [PATCH v3] net: atlantic: always deep reset on pm op, fixing null deref regression References: <8735hniqcm.fsf@posteo.de> <833f2574-daf6-1357-d865-3528436ba393@leemhuis.info> <87bkw91ob6.fsf@posteo.de> <4b99fc01-5ab4-d803-4177-a1402ac98164@leemhuis.info> Date: Sat, 07 May 2022 14:00:10 +0000 In-Reply-To: <4b99fc01-5ab4-d803-4177-a1402ac98164@leemhuis.info> (Thorsten Leemhuis's message of "Sat, 7 May 2022 15:25:51 +0200") Message-ID: <874k211lzp.fsf@posteo.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Thorsten Leemhuis writes: > On 07.05.22 15:10, Manuel Ullmann wrote: >> Thorsten Leemhuis writes: >>=20 >>> On 06.05.22 00:09, Manuel Ullmann wrote: >>>> >From d24052938345d456946be0e9ccc337e24d771c79 Mon Sep 17 00:00:00 2001 >>>> Date: Wed, 4 May 2022 21:30:44 +0200 >>>> >>>> The impact of this regression is the same for resume that I saw on >>>> thaw: the kernel hangs and nothing except SysRq rebooting can be done. >>>> >>>> The null deref occurs at the same position as on thaw. >>>> BUG: kernel NULL pointer dereference >>>> RIP: aq_ring_rx_fill+0xcf/0x210 [atlantic] >>>> >>>> Fixes regression in commit cbe6c3a8f8f4 ("net: atlantic: invert deep >>>> par in pm functions, preventing null derefs"), where I disabled deep >>>> pm resets in suspend and resume, trying to make sense of the >>>> atl_resume_common deep parameter in the first place. >>>> >>>> It turns out, that atlantic always has to deep reset on pm operations >>>> and the parameter is useless. Even though I expected that and tested >>>> resume, I screwed up by kexec-rebooting into an unpatched kernel, thus >>>> missing the breakage. >>>> >>>> This fixup obsoletes the deep parameter of atl_resume_common, but I >>>> leave the cleanup for the maintainers to post to mainline. >>> >>> FWIW, this section starting here and... >>> >>>> PS: I'm very sorry for this regression. >>>> >>>> Changes in v2: >>>> Patch formatting fixes >>>> - Fix Fixes tag >>>> =E2=80=93 Simplify stable Cc tag >>>> =E2=80=93 Fix Signed-off-by tag >>>> >>>> Changes in v3: >>>> =E2=80=93 Prefixed commit reference with "commit" aka I managed to use >>>> checkpatch.pl. >>>> - Added Tested-by tags for the testing reporters. >>>> =E2=80=93 People start to get annoyed by my patch revision spamming. S= hould be >>>> the last one. >>> >>> ...ending here needs should be below the "---" line you already have >>> below. For details see: >>> https://www.kernel.org/doc/html/latest/process/submitting-patches.html > > Sorry, I caused a misunderstanding. I didn't handle the above, I'm not > one of the net subsystem developers. Either you submit a v4 fixing this > or hope the net maintainer take care of that when they look at it -- but > I guess they would highly prefer it if you'd address this. Never mind. Then I=E2=80=99ll post a v4. Thanks for handling the regzbot tracking. I indeed just assumed this already to be correctly regzbot tracked. Never post in a hurry. >>> BTW, same goes for any "#regzbot" commands (like you had in >>> cbe6c3a8f8f4), as things otherwise get confused when a patch for example >>> is posted as part of a stable/longterm -rc review. >> Good to know. Maybe I could patch the handling-regressions documentation >> to include this. > > Yeah, I have already thought about it, but didn't get down to it yet. Well, I could try it eventually. > Only so much hours in a day. I know that issue. ;) >> submitting-patches could also link the subsystem >> specific documentation, e.g. the netdev FAQ, since they handle patches >> with their more bot tests. Would have helped me a bit. Might be a nice >> exercise for properly formatted patching ;) > > I agree that the docs for submitting patches could need a few > improvements and that is likely one of them. Then I=E2=80=99ll try fixing this, too. After all most devs have scarce tim= e for documentation. >>> But don't worry, no big deal, I handled that :-D Many thx for actually >>> directly getting regzbot involved and taking care of this regression! >> Thank you for the final cleanup and you=E2=80=99re welcome. :) Where did= you >> handle this? I can=E2=80=99t seem to find the fixup anywhere, i.e. net-n= ext, >> net, linux-next or lkml. > > See above, I only handled the regzbot issue, not the issue with this > patch. Sorry for not being clear enough in my wording. Thanks for clearing this up. Regards, Manuel