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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 242FAC43463 for ; Thu, 17 Sep 2020 23:09:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0611207FB for ; Thu, 17 Sep 2020 23:09:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZcKYikLq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725858AbgIQXI7 (ORCPT ); Thu, 17 Sep 2020 19:08:59 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:47392 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726004AbgIQXI7 (ORCPT ); Thu, 17 Sep 2020 19:08:59 -0400 X-Greylist: delayed 74755 seconds by postgrey-1.27 at vger.kernel.org; Thu, 17 Sep 2020 19:08:58 EDT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600384138; 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: in-reply-to:in-reply-to:references:references; bh=uzfwQDrkfORvWeEWQ/DT80gvpbqXcqJubxjDGJKPNLI=; b=ZcKYikLqug1Id/n/rJB3efIgxGGK4oa8QtAKzr3EiB+dNHrJGT5dTO1xH7R1yVDe7uxZgJ MEQ9Z8s/ZOQpGh947XlqE0Bnb5dEbk/iAcHnElo2Vg7HYJ/X9+4Tro/bOGqBR6EkFhB1nf PbBmGLYQqgDrk+LalSbOEkOpdBF3GjA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-561-euwv-xhLMlWa5iZ5HdKl-w-1; Thu, 17 Sep 2020 19:08:56 -0400 X-MC-Unique: euwv-xhLMlWa5iZ5HdKl-w-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C25F01882FB0; Thu, 17 Sep 2020 23:08:54 +0000 (UTC) Received: from T590 (ovpn-12-51.pek2.redhat.com [10.72.12.51]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C42D055769; Thu, 17 Sep 2020 23:08:46 +0000 (UTC) Date: Fri, 18 Sep 2020 07:08:42 +0800 From: Ming Lei To: "Theodore Y. Ts'o" Cc: Jens Axboe , linux-ext4@vger.kernel.org, "linux-kernel@vger.kernel.org" , linux-block@vger.kernel.org, Linus Torvalds Subject: Re: REGRESSION: 37f4a24c2469: blk-mq: centralise related handling into blk_mq_get_driver_tag Message-ID: <20200917230842.GA1139137@T590> References: <5140ba6c-779c-2a71-b7f2-3c3220cdf19c@kernel.dk> <68510957-c887-8e26-4a1a-a7a93488586a@kernel.dk> <20200904035528.GE558530@mit.edu> <20200915044519.GA38283@mit.edu> <20200915073303.GA754106@T590> <20200915224541.GB38283@mit.edu> <20200915230941.GA791425@T590> <20200916202026.GC38283@mit.edu> <20200917022051.GA1004828@T590> <20200917143012.GF38283@mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200917143012.GF38283@mit.edu> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Thu, Sep 17, 2020 at 10:30:12AM -0400, Theodore Y. Ts'o wrote: > On Thu, Sep 17, 2020 at 10:20:51AM +0800, Ming Lei wrote: > > > > Obviously there is other more serious issue, since 568f27006577 is > > completely reverted in your test, and you still see list corruption > > issue. > > > > So I'd suggest to find the big issue first. Once it is fixed, maybe > > everything becomes fine. > > ... > > Looks it is more like a memory corruption issue, is there any helpful log > > dumped when running kernel with kasan? > > Last night, I ran six VM's using -rc4 with and without KASAN; without > Kasan, half of them hung. With KASAN enabled, all of the test VM's > ran to completion. >From your last email, when you run -rc4 with revert of 568f27006577, you can observe list corruption easily. So can you enable KASAN on -rc4 with revert of 568f27006577 and see if it makes a difference? > > This strongly suggests whatever the problem is, it's timing related. > I'll run a larger set of test runs to see if this pattern is confirmed > today. Looks you enable lots of other debug options, such a lockdep, which has much much heavy runtime load. Maybe you can disable all non-KASAN debug option(non-KASAN memory debug options, lockdep, ...) and keep KASAN debug only and see if you are lucky. Thanks, Ming