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 EFC3CC43334 for ; Mon, 20 Jun 2022 10:10:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239833AbiFTKKU (ORCPT ); Mon, 20 Jun 2022 06:10:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42018 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234353AbiFTKKT (ORCPT ); Mon, 20 Jun 2022 06:10:19 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B868E643B; Mon, 20 Jun 2022 03:10:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5229460EC6; Mon, 20 Jun 2022 10:10:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D14AC3411B; Mon, 20 Jun 2022 10:10:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655719817; bh=j2gcVScnAnCRh9va+iai+mbgmOG2AkHu0Y3qUq9Hmzc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fnlL+avNTPoMd9eMBKlGly5Uw4LR38zebf9Eylf5/R0EKbZJGOUQQCGIQgujsdm64 DJLS5AXzAKE3MtEyPbdrUqcmb8xLNFD2cyp6sAQcfBEi1M+E9E8hp4p5sPLD8Hs8Do 8Rbg58erSKcgR5szIFetRzmKwmf3qtCn19U40y1U= Date: Mon, 20 Jun 2022 12:10:15 +0200 From: Greg Kroah-Hartman To: Coly Li Cc: Pavel Machek , Pavel Machek , Naresh Kamboju , baijiaju1990@gmail.com, oslab@tsinghua.edu.cn, Jens Axboe , linux-kernel@vger.kernel.org, stable@vger.kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, linux@roeck-us.net, shuah@kernel.org, patches@kernelci.org, lkft-triage@lists.linaro.org, jonathanh@nvidia.com, f.fainelli@gmail.com, sudipm.mukherjee@gmail.com, slade@sladewatkins.com, Daniel Latypov , Brendan Higgins , kunit-dev@googlegroups.com, "open list:KERNEL SELFTEST FRAMEWORK" Subject: Re: [PATCH 5.17 000/772] 5.17.14-rc1 review Message-ID: References: <20220607164948.980838585@linuxfoundation.org> <20220618104925.GA3644@duo.ucw.cz> <6497730E-D4D2-4FB3-B95B-E1DAB2C2B287@suse.de> <20220618113703.GA10888@duo.ucw.cz> <186E5519-55D4-48EE-8599-2C863BEC3918@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <186E5519-55D4-48EE-8599-2C863BEC3918@suse.de> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Sat, Jun 18, 2022 at 07:57:01PM +0800, Coly Li wrote: > > > > 2022年6月18日 19:37，Pavel Machek 写道： > > > > Hi! > > > >>>> Fixes: bc082a55d25c ("bcache: fix inaccurate io state for detached > >>> ... > >>> > >>>> +++ b/drivers/md/bcache/request.c > >>>> @@ -1107,6 +1107,12 @@ static void detached_dev_do_request(struct > >>>> bcache_device *d, struct bio *bio, > >>>> * which would call closure_get(&dc->disk.cl) > >>>> */ > >>>> ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO); > >>>> + if (!ddip) { > >>>> + bio->bi_status = BLK_STS_RESOURCE; > >>>> + bio->bi_end_io(bio); > >>>> + return; > >>>> + } > >>>> + > >>>> ddip->d = d; > >>>> /* Count on the bcache device */ > >>>> ddip->orig_bdev = orig_bdev; > >>>> > >>> > >>> So... for patch to make any difference, memory allocation has to fail > >>> and ddip has to be NULL. > >>> > >>> Before the patch, it would oops in "ddip->d = d;". With the patch, you > >>> do some kind of error handling. Even if it is buggy, it should not do > >>> more harm than immediate oops. > >> > >> I just receive this single email and don’t have any idea for the context and what the problem is. Where can I see the whole conversation? > >> > > > > Discussion happened on stable@vger.kernel.org mailing lists, archives > > should be easily available. Copy went to lkml, too. > > Hi Pavel and Greg, > > Thanks for the hint, I see the context. I cannot tell the direct reason of the kfence regression, but it is worthy to have this patch in, > - commit 7d6b902ea0e0 ("bcache: memset on stack variables in bch_btree_check() and bch_sectors_dirty_init()”) > > I am not sure whether it is directly related to the kfence issue, it corrects potential unexpected stack state in some condition. Hope it may help a bit. Added where? confused, greg k-h