From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0FB74C432C0 for ; Mon, 25 Nov 2019 02:21:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C600A20718 for ; Mon, 25 Nov 2019 02:21:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=netronome-com.20150623.gappssmtp.com header.i=@netronome-com.20150623.gappssmtp.com header.b="gH4v+ctB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726945AbfKYCVf (ORCPT ); Sun, 24 Nov 2019 21:21:35 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:36237 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726875AbfKYCVf (ORCPT ); Sun, 24 Nov 2019 21:21:35 -0500 Received: by mail-pf1-f195.google.com with SMTP id b19so6607348pfd.3 for ; Sun, 24 Nov 2019 18:21:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :organization:mime-version:content-transfer-encoding; bh=0Slbk7FHKESeFqcEuY8H04LKnF7/drC0hQa4BJ/FDvg=; b=gH4v+ctBIPNMcQL86nKHecbkeJwpsrU/V3M2WbEfwawz+TRk/u6ND6wuIqXpt6t8t9 5a5Y8zWBllvB5EANzgYSeR2+KsJsQpZHsYDqW6ELNTnyBqgwqfYnJV81PgeJHndccNjb igkz2bEdeFgZfOcnb6h1x+XIoXWn6FI84lA6bN1lHNmcLKElj1bRzDzmn2PTws27jfdL BOiw0PZjJ/8lC5NygqkGOJUbJujon5jBOxkEwQiI166JObmhx3FlUyiMuhAgBVrF0BLl WwsjasT/v0ktfcRkUltnpCnu/xXr4ShmWiNVv8KMI2qPFPar2t1eB/8WW9JAV8PxD6R1 QsFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:organization:mime-version:content-transfer-encoding; bh=0Slbk7FHKESeFqcEuY8H04LKnF7/drC0hQa4BJ/FDvg=; b=LQojJ898z9gZe1X0LOkg1pS/nDnU098JgVqxsbiaOEnDGCO1bNwKPHuolRoqDymR8M ScPlSnkTP7GmHuIpryRoL9tD+qGyctihyOvRye6/bWRMCfT0yax6b5+4rik7MJJ2WMCL g89MIsGfINSwAQvHU0yi1Z1mYpk2okRsSQIa+pX+Z9A3Zg9H0y+pTemZFTzrQLK30vdL K7jPxFNz7S7Cbnqrr+O7qu1Oxj8j/6SgERgOgKujXYkJtC8yvjatWJ6m9IfTpDtTsT4I W/6mVUy7RNrUnp9nfM7z6fnMpS85cG88gPx5XtHsQ5I0fDZk7mnwWL6D1SjBdf0agBp6 CcQQ== X-Gm-Message-State: APjAAAXW9z/E7RQV2YoQqjw+zkGcpvrm1osSv+P9JNfQkeqIir4/7nJD Y3TGWDSHDARFxuX6/jes0gnKHg== X-Google-Smtp-Source: APXvYqy2NXWAYVFU4lF8cJY4DfT9esmtA2nl94dpzBrdQ+ER0JKUb0rxNsKuqL7Yn5+iqaTu/PgtcQ== X-Received: by 2002:a63:6705:: with SMTP id b5mr30162797pgc.23.1574648494395; Sun, 24 Nov 2019 18:21:34 -0800 (PST) Received: from cakuba.netronome.com (c-73-202-202-92.hsd1.ca.comcast.net. [73.202.202.92]) by smtp.gmail.com with ESMTPSA id x2sm5822449pgc.67.2019.11.24.18.21.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 24 Nov 2019 18:21:34 -0800 (PST) Date: Sun, 24 Nov 2019 18:21:28 -0800 From: Jakub Kicinski To: Chuhong Yuan Cc: Nicolas Ferre , "David S . Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net v3] net: macb: add missed tasklet_kill Message-ID: <20191124182113.481f984b@cakuba.netronome.com> In-Reply-To: <20191123141918.16239-1-hslester96@gmail.com> References: <20191123141918.16239-1-hslester96@gmail.com> Organization: Netronome Systems, Ltd. MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 23 Nov 2019 22:19:18 +0800, Chuhong Yuan wrote: > This driver forgets to kill tasklet in remove. > Add the call to fix it. > > Fixes: 032dc41ba6e2 ("net: macb: Handle HRESP error") > Signed-off-by: Chuhong Yuan I think this leaves a race condition, as far as I can tell tasklet_kill() just kills the currently scheduled tasklet, but doesn't prevent it from being scheduled again. If the interrupt fires just after the tasklet_kill() call the tasklet will be scheduled back in. I think you'd need to mask the interrupt (through the IDR register?) or just put the tasklet_kill() call after unregister_netdev(), because AFAICT closing the netdev disables all irqs. > diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c > index 1e1b774e1953..2ec416098fa3 100644 > --- a/drivers/net/ethernet/cadence/macb_main.c > +++ b/drivers/net/ethernet/cadence/macb_main.c > @@ -4383,6 +4383,7 @@ static int macb_remove(struct platform_device *pdev) > > if (dev) { > bp = netdev_priv(dev); > + tasklet_kill(&bp->hresp_err_tasklet); > if (dev->phydev) > phy_disconnect(dev->phydev); > mdiobus_unregister(bp->mii_bus);