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=-4.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 EAE26C76190 for ; Tue, 23 Jul 2019 23:25:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C207422387 for ; Tue, 23 Jul 2019 23:25:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563924306; bh=FGNG2bsI180IX9yfVVejxvvKc6LPkLx7d3W+nSaEtYY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=gJcOOHOxGxeY5GOep1CkQ9bLFzNhTMg0oBefyzHiQ9NYlUo2yAHUJIPt7CifD9mCK gK/2B/TEnOb0ZUk/HdEob96WgkuJYp5pJhDKRaW5e2hn5uprKiGiM4Dg5B8OAKWjoy jJ8B70mFE2kTds056LxrBg22I+p3N/pnH/40Sh5Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726816AbfGWXZF (ORCPT ); Tue, 23 Jul 2019 19:25:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:41800 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726438AbfGWXZF (ORCPT ); Tue, 23 Jul 2019 19:25:05 -0400 Received: from gmail.com (unknown [104.132.1.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CE1AB2253D; Tue, 23 Jul 2019 23:25:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563924304; bh=FGNG2bsI180IX9yfVVejxvvKc6LPkLx7d3W+nSaEtYY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MmKZKEj9rYYuSx5IhPuVqW3yDLIXTJo+2Pjo8kn2rXJQRI0BajWjrOke5jXiV/Myq KkhnD1MWfZQbxAaTDQvQWLNNBmhF1dZIuAcp4Ha09rkCKnFHgdoOJB121myzkHrs7P Yd0vHiCvZb0zZO+CZbS9JAzOgO2NtIXCSPxE+R/o= Date: Tue, 23 Jul 2019 16:25:02 -0700 From: Eric Biggers To: Andrew Morton Cc: syzbot , catalin.marinas@arm.com, davem@davemloft.net, dvyukov@google.com, jack@suse.com, kirill.shutemov@linux.intel.com, koct9i@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-rdma@vger.kernel.org, neilb@suse.de, netdev@vger.kernel.org, rds-devel@oss.oracle.com, ross.zwisler@linux.intel.com, santosh.shilimkar@oracle.com, syzkaller-bugs@googlegroups.com, torvalds@linux-foundation.org, willy@linux.intel.com Subject: Re: memory leak in rds_send_probe Message-ID: <20190723232500.GA71043@gmail.com> Mail-Followup-To: Andrew Morton , syzbot , catalin.marinas@arm.com, davem@davemloft.net, dvyukov@google.com, jack@suse.com, kirill.shutemov@linux.intel.com, koct9i@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-rdma@vger.kernel.org, neilb@suse.de, netdev@vger.kernel.org, rds-devel@oss.oracle.com, ross.zwisler@linux.intel.com, santosh.shilimkar@oracle.com, syzkaller-bugs@googlegroups.com, torvalds@linux-foundation.org, willy@linux.intel.com References: <000000000000ad1dfe058e5b89ab@google.com> <00000000000034c84a058e608d45@google.com> <20190723152336.29ed51551d8c9600bb316b52@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190723152336.29ed51551d8c9600bb316b52@linux-foundation.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 23, 2019 at 03:23:36PM -0700, Andrew Morton wrote: > On Tue, 23 Jul 2019 15:17:00 -0700 syzbot wrote: > > > syzbot has bisected this bug to: > > > > commit af49a63e101eb62376cc1d6bd25b97eb8c691d54 > > Author: Matthew Wilcox > > Date: Sat May 21 00:03:33 2016 +0000 > > > > radix-tree: change naming conventions in radix_tree_shrink > > > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=176528c8600000 > > start commit: c6dd78fc Merge branch 'x86-urgent-for-linus' of git://git... > > git tree: upstream > > final crash: https://syzkaller.appspot.com/x/report.txt?x=14e528c8600000 > > console output: https://syzkaller.appspot.com/x/log.txt?x=10e528c8600000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=8de7d700ea5ac607 > > dashboard link: https://syzkaller.appspot.com/bug?extid=5134cdf021c4ed5aaa5f > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=145df0c8600000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=170001f4600000 > > > > Reported-by: syzbot+5134cdf021c4ed5aaa5f@syzkaller.appspotmail.com > > Fixes: af49a63e101e ("radix-tree: change naming conventions in > > radix_tree_shrink") > > > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > > That's rather hard to believe. af49a63e101eb6237 simply renames a > couple of local variables. > It's been known for months (basically ever since bisection was added) that about 50% of syzbot bisection results are obviously incorrect, often a commit selected at random. Unfortunately, the people actually funded to work on syzbot apparently don't consider fixing this to be high priority issue, so we have to live with it for now. Or until someone volunteers to fix it themselves; source is at https://github.com/google/syzkaller. So for now, please don't waste much time on bisection results that look wonky. But please do pay attention to any bisection results in reminders I've been sending like "Reminder: 10 open syzbot bugs in foo subsystem", since I've manually reviewed those to exclude the obviously wrong results... - Eric