Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753454AbbDBSI5 (ORCPT ); Thu, 2 Apr 2015 14:08:57 -0400 Received: from shards.monkeyblade.net ([149.20.54.216]:40194 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752208AbbDBSIy (ORCPT ); Thu, 2 Apr 2015 14:08:54 -0400 Date: Thu, 02 Apr 2015 14:08:50 -0400 (EDT) Message-Id: <20150402.140850.1775436517754499795.davem@davemloft.net> To: sowmini.varadhan@oracle.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, chien.yen@oracle.com, rds-devel@oss.oracle.com, agrover@redhat.com, clm@fb.com, zab@zabbo.net, ajaykumar.hotchandani@oracle.com, sergei.shtylyov@cogentembedded.com Subject: Re: [PATCHv2 3/6] rds: check for excessive looping in rds_send_xmit From: David Miller In-Reply-To: <5f877b89716358c7a08272275979b5e039ca1c29.1427983908.git.sowmini.varadhan@oracle.com> References: <5f877b89716358c7a08272275979b5e039ca1c29.1427983908.git.sowmini.varadhan@oracle.com> X-Mailer: Mew version 6.5 on Emacs 24.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Thu, 02 Apr 2015 11:08:53 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1068 Lines: 36 From: Sowmini Varadhan Date: Thu, 2 Apr 2015 10:19:37 -0400 > @@ -177,6 +178,18 @@ int rds_send_xmit(struct rds_connection *conn) > > rm = conn->c_xmit_rm; > > + if (!rm) { > + same_rm = 0; > + } else { > + same_rm++; > + if (same_rm >= 4096) { > + printk_ratelimited(KERN_ERR "RDS: Stuck rm\n"); > + cond_resched(); > + ret = -EAGAIN; > + break; > + } > + } > + I'm not accepting junk like this. I want to know exactly how this situation can occur, in detail, and then and only then can we start to talk about more reasonable solutions to this bug. This looks like a minimal effort hack to make a hang go away, and even more concerning is that a change like this is submitted with a commit message that is essentially empty. Sorry, this is not acceptable. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/