From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933024AbcBIQdc (ORCPT ); Tue, 9 Feb 2016 11:33:32 -0500 Received: from smtprelay0009.hostedemail.com ([216.40.44.9]:59848 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932607AbcBIQda (ORCPT ); Tue, 9 Feb 2016 11:33:30 -0500 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,rostedt@goodmis.org,:::::::::,RULES_HIT:41:355:379:541:599:800:960:973:988:989:1260:1277:1311:1313:1314:1345:1359:1437:1515:1516:1518:1534:1538:1593:1594:1711:1714:1730:1747:1777:1792:2393:2553:2559:2562:2903:3138:3139:3140:3141:3142:3351:3622:3865:3866:3867:3868:3870:3871:3874:5007:6119:6261:7875:7903:10004:10400:10450:10455:10848:10967:11232:11658:11914:12296:12517:12519:12740:13069:13311:13357:14659:19904:19999:21080:21324:30012:30051:30054:30090:30091,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:2,LUA_SUMMARY:none X-HE-Tag: hose87_58715d734cf1c X-Filterd-Recvd-Size: 1669 Date: Tue, 9 Feb 2016 11:33:26 -0500 From: Steven Rostedt To: Denys Vlasenko Cc: linux-kernel@vger.kernel.org, srostedt@redhat.com, Tejun Heo , Peter Hurley Subject: Re: [PATCH] printk: avoid livelock if another CPU printks continuously Message-ID: <20160209113326.501867bc@gandalf.local.home> In-Reply-To: <56BA0ECE.2050106@redhat.com> References: <1454963703-20433-1-git-send-email-dvlasenk@redhat.com> <20160208161123.2ceb601d@gandalf.local.home> <56B9FEE4.3010502@redhat.com> <20160209101707.540641fb@gandalf.local.home> <56BA04AD.7090903@redhat.com> <20160209105024.3606f233@gandalf.local.home> <56BA0ECE.2050106@redhat.com> X-Mailer: Claws Mail 3.13.1 (GTK+ 2.24.29; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 09 Feb 2016 17:07:42 +0100 Denys Vlasenko wrote: > On 02/09/2016 04:50 PM, Steven Rostedt wrote: > > One thing is to find the spamming code and fix that. > > We can't rely that there won't be never-ending concurrent printks, > right? For one, in many setups user can cause printk flood. No, that would be a bug. This is why we have printk_ratelimit for. > > I think we must ensure that printk does not livelock. printk is a kernel utility. The users of printk must ensure this. -- Steve