From patchwork Sun Mar 29 23:32:34 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Larry Finger X-Patchwork-Id: 25295 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id D90CEDDDB2 for ; Mon, 30 Mar 2009 10:32:56 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753116AbZC2Xco (ORCPT ); Sun, 29 Mar 2009 19:32:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751582AbZC2Xco (ORCPT ); Sun, 29 Mar 2009 19:32:44 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:53656 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751390AbZC2Xcn (ORCPT ); Sun, 29 Mar 2009 19:32:43 -0400 Received: from larrylap ([69.76.240.125]) by hrndva-omta04.mail.rr.com with SMTP id <20090329233239.XULA23691.hrndva-omta04.mail.rr.com@larrylap>; Sun, 29 Mar 2009 23:32:39 +0000 Date: Sun, 29 Mar 2009 18:32:34 -0500 From: Larry Finger To: jgarzik@pobox.com Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 1/2] kaweth: Fix locking to be SMP-safe Message-ID: <49d00512.XAF19LdpY1dlK6+U%Larry.Finger@lwfinger.net> User-Agent: Heirloom mailx 12.2 01/07/07 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On an SMP system, the following message is printed. The patch below gets fixes the problem. --- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html ================================= [ INFO: inconsistent lock state ] 2.6.29-Linus-05093-gc31f403 #57 --------------------------------- inconsistent {hardirq-on-W} -> {in-hardirq-W} usage. bash/4105 [HC1[1]:SC0[0]:HE0:SE1] takes: (&kaweth->device_lock){+...}, at: [] kaweth_usb_receive+0x77/0x1af [kaw eth] {hardirq-on-W} state was registered at: [] __lock_acquire+0x753/0x1685 [] lock_acquire+0x55/0x71 [] _spin_lock+0x31/0x3d [] kaweth_start_xmit+0x2b/0x1e1 [kaweth] [] dev_hard_start_xmit+0x22e/0x2ad [] __qdisc_run+0xf2/0x203 [] dev_queue_xmit+0x263/0x39b [] packet_sendmsg_spkt+0x1c4/0x20a [af_packet] [] sock_sendmsg+0xe4/0xfd [] sys_sendto+0xe4/0x10c [] system_call_fastpath+0x16/0x1b [] 0xffffffffffffffff irq event stamp: 1280 hardirqs last enabled at (1279): [] _spin_unlock_irqrestore+0x44/0x4c hardirqs last disabled at (1280): [] save_args+0x67/0x70 softirqs last enabled at (660): [] __do_softirq+0x14d/0x15d softirqs last disabled at (651): [] call_softirq+0x1c/0x28 Signed-off-by: Larry Finger --- Jeff, As the listed authors of this driver have not touched it in several years, I have taken the liberty of sending it to you as networking drivers maintainer. I hope this is OK. Larry --- Index: wireless-testing/drivers/net/usb/kaweth.c =================================================================== --- wireless-testing.orig/drivers/net/usb/kaweth.c +++ wireless-testing/drivers/net/usb/kaweth.c @@ -36,7 +36,6 @@ * Run test procedures * Fix bugs from previous two steps * Snoop other OSs for any tricks we're not doing - * SMP locking * Reduce arbitrary timeouts * Smart multicast support * Temporary MAC change support @@ -529,6 +528,7 @@ static void int_callback(struct urb *u) goto resubmit; } + spin_lock(&kaweth->device_lock); /* we check the link state to report changes */ if (kaweth->linkstate != (act_state = ( kaweth->intbuffer[STATE_OFFSET] | STATE_MASK) >> STATE_SHIFT)) { if (act_state) @@ -540,6 +540,7 @@ static void int_callback(struct urb *u) } resubmit: kaweth_resubmit_int_urb(kaweth, GFP_ATOMIC); + spin_unlock(&kaweth->device_lock); } static void kaweth_resubmit_tl(struct work_struct *work) @@ -606,21 +607,19 @@ static void kaweth_usb_receive(struct ur __u16 pkt_len = le16_to_cpup((__le16 *)kaweth->rx_buf); struct sk_buff *skb; + unsigned long flags; + spin_lock_irqsave(&kaweth->device_lock, flags); if(unlikely(status == -ECONNRESET || status == -ESHUTDOWN)) /* we are killed - set a flag and wake the disconnect handler */ { kaweth->end = 1; wake_up(&kaweth->term_wait); - return; + goto out; } - spin_lock(&kaweth->device_lock); - if (IS_BLOCKED(kaweth->status)) { - spin_unlock(&kaweth->device_lock); - return; - } - spin_unlock(&kaweth->device_lock); + if (IS_BLOCKED(kaweth->status)) + goto out; if(status && status != -EREMOTEIO && count != 1) { err("%s RX status: %d count: %d packet_len: %d", @@ -629,7 +628,7 @@ static void kaweth_usb_receive(struct ur count, (int)pkt_len); kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC); - return; + goto out; } if(kaweth->net && (count > 2)) { @@ -638,12 +637,12 @@ static void kaweth_usb_receive(struct ur err("Packet len & 2047: %x", pkt_len & 2047); err("Count 2: %x", count2); kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC); - return; + goto out; } if(!(skb = dev_alloc_skb(pkt_len+2))) { kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC); - return; + goto out; } skb_reserve(skb, 2); /* Align IP on 16 byte boundaries */ @@ -661,6 +660,8 @@ static void kaweth_usb_receive(struct ur } kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC); +out: + spin_unlock_irqrestore(&kaweth->device_lock, flags); } /**************************************************************** @@ -778,12 +779,14 @@ static void kaweth_usb_transmit_complete struct sk_buff *skb = kaweth->tx_skb; int status = urb->status; + spin_lock(&kaweth->device_lock); if (unlikely(status != 0)) if (status != -ENOENT) dbg("%s: TX status %d.", kaweth->net->name, status); netif_wake_queue(kaweth->net); dev_kfree_skb_irq(skb); + spin_unlock(&kaweth->device_lock); } /**************************************************************** @@ -796,7 +799,7 @@ static int kaweth_start_xmit(struct sk_b int res; - spin_lock(&kaweth->device_lock); + spin_lock_irq(&kaweth->device_lock); kaweth_async_set_rx_mode(kaweth); netif_stop_queue(net); @@ -814,7 +817,7 @@ static int kaweth_start_xmit(struct sk_b if (!copied_skb) { kaweth->stats.tx_errors++; netif_start_queue(net); - spin_unlock(&kaweth->device_lock); + spin_unlock_irq(&kaweth->device_lock); return 0; } } @@ -848,7 +851,7 @@ skip: net->trans_start = jiffies; } - spin_unlock(&kaweth->device_lock); + spin_unlock_irq(&kaweth->device_lock); return 0; }