From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [Kernel][NET] Bug report on packet defragmenting Date: Wed, 7 Nov 2018 17:43:09 -0800 Message-ID: <91b43bec-cb19-b94b-8ee3-26979e3a19d1@gmail.com> References: <20181108012927epcms1p47f719c1908da64a378690362901644ee@epcms1p4> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit To: soukjin.bae@samsung.com, "netdev@vger.kernel.org" Return-path: Received: from mail-pg1-f170.google.com ([209.85.215.170]:34763 "EHLO mail-pg1-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728328AbeKHLQP (ORCPT ); Thu, 8 Nov 2018 06:16:15 -0500 Received: by mail-pg1-f170.google.com with SMTP id k1-v6so8133058pgq.1 for ; Wed, 07 Nov 2018 17:43:13 -0800 (PST) In-Reply-To: <20181108012927epcms1p47f719c1908da64a378690362901644ee@epcms1p4> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 11/07/2018 05:29 PM, 배석진 wrote: > If ipv6_defrag hook is not excuted simultaneously, then it's ok. > ipv6_defrag hook can handle that. [exam 3] This seems wrong. This is the root cause, we should not try to work around it but fix it. There is no guarantee that RSS/RPS/RFS can help here, packets can sit in per-cpu backlogs long enough to reproduce the issue, if RX queues interrupts are spread over many cpus.