Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933390AbdDGSma (ORCPT ); Fri, 7 Apr 2017 14:42:30 -0400 Received: from shards.monkeyblade.net ([184.105.139.130]:58900 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754895AbdDGSmW (ORCPT ); Fri, 7 Apr 2017 14:42:22 -0400 Date: Fri, 07 Apr 2017 11:42:16 -0700 (PDT) Message-Id: <20170407.114216.29873489271414092.davem@davemloft.net> To: eric.dumazet@gmail.com Cc: ville.syrjala@linux.intel.com, edumazet@google.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [regression v4.11] 617f01211baf ("8139too: use napi_complete_done()") From: David Miller In-Reply-To: <1491590329.10124.86.camel@edumazet-glaptop3.roam.corp.google.com> References: <20170407181754.GL30290@intel.com> <1491590329.10124.86.camel@edumazet-glaptop3.roam.corp.google.com> X-Mailer: Mew version 6.7 on Emacs 25.1 / 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]); Fri, 07 Apr 2017 11:01:03 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 386 Lines: 11 From: Eric Dumazet Date: Fri, 07 Apr 2017 11:38:49 -0700 > I do not really see what could be wrong, the code should run just fine > on UP. One theory is that the interrupt masking isn't working properly and interrupts are still arriving and hitting the NAPI state even when we are actively polling NAPI. And this problem was masked by the locking done here.