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=-0.8 required=3.0 tests=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 48F9BC433FF for ; Wed, 31 Jul 2019 15:19:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2969B206A2 for ; Wed, 31 Jul 2019 15:19:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729735AbfGaPTu (ORCPT ); Wed, 31 Jul 2019 11:19:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41918 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726691AbfGaPTt (ORCPT ); Wed, 31 Jul 2019 11:19:49 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 534D2308FC4B; Wed, 31 Jul 2019 15:19:49 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-120-255.rdu2.redhat.com [10.10.120.255]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8A9DE5D9C5; Wed, 31 Jul 2019 15:19:47 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <0000000000004c2416058c594b30@google.com> <24282.1562074644@warthog.procyon.org.uk> <20330.1564583454@warthog.procyon.org.uk> To: Dmitry Vyukov Cc: dhowells@redhat.com, syzbot , Eric Biggers , David Miller , linux-afs@lists.infradead.org, LKML , netdev , syzkaller-bugs Subject: Re: kernel BUG at net/rxrpc/local_object.c:LINE! MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <22317.1564586386.1@warthog.procyon.org.uk> Date: Wed, 31 Jul 2019 16:19:46 +0100 Message-ID: <22318.1564586386@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Wed, 31 Jul 2019 15:19:49 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Dmitry Vyukov wrote: > Please send a patch for testing that enables this tracing > unconditionally. This should have the same effect. There is no way to > hook into a middle of the automated process and arbitrary tune things. I don't know how to do that off hand. Do you have an example? Anyway, I think rxrpc_local_processor() is broken with respect to refcounting as it gets scheduled when usage==0, but that doesn't stop it being rescheduled again by a network packet before it manages to close the UDP socket. David