From mboxrd@z Thu Jan 1 00:00:00 1970 From: Prarit Bhargava Subject: Re: [PATCH]: Add Network Sysrq Support Date: Wed, 22 Jun 2011 08:19:33 -0400 Message-ID: <4E01DDD5.8020707@redhat.com> References: <20110621130040.12035.62533.sendpatchset@prarit.bos.redhat.com> <4E0115B3.2030802@redhat.com> <20110621225645.GD16021@Chamillionaire.breakpoint.cc> <20110621.155816.1840729860084652508.davem@davemloft.net> <4E01C34F.6050009@redhat.com> <20110622105434.GE16021@Chamillionaire.breakpoint.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: David Miller , fbl@redhat.com, netdev@vger.kernel.org, agospoda@redhat.com, nhorman@redhat.com, lwoodman@redhat.com, john.haxby@oracle.com To: Florian Westphal Return-path: Received: from mx1.redhat.com ([209.132.183.28]:33806 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753924Ab1FVMTo (ORCPT ); Wed, 22 Jun 2011 08:19:44 -0400 In-Reply-To: <20110622105434.GE16021@Chamillionaire.breakpoint.cc> Sender: netdev-owner@vger.kernel.org List-ID: On 06/22/2011 06:54 AM, Florian Westphal wrote: > Prarit Bhargava wrote: > > [ cc'd John Haxby, who worked on xt_SYSREQ ] > > >> On 06/21/2011 06:58 PM, David Miller wrote: >> >>> From: Florian Westphal >>> Date: Wed, 22 Jun 2011 00:56:45 +0200 >>> >>>> This is one of the reasons why I still think that >>>> xt_SYSREQ would be the better solution, you get all >>>> kinds of filtering features for free. >>>> >>>> You could even use crazy things like '-m time' to restrict >>>> sysreq availability to working hours and whatnot. >>>> >>>> >>> Agreed. >>> >> Using the netfilter xt-SYSRQ code seems to store the entered code and >> execute it later after the system has returned to a normal state.... >> which is much too late to be useful. >> > The target handler of the kernel part invokes handle_sysrq(), > I don't see any delaying/queueing? > Yeah ... It just occurred to me on the way into the office that I made a mistake. ... What if the "slow down" I'm seeing is due to the network layer? ... but why would ping work and the xt_SYSRQ not work? Either way ... I have a feeling that I'm on to something, P.