From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: [PATCH] e1000: Avoid that e1000_netpoll() triggers a kernel warning Date: Thu, 9 Apr 2015 13:54:45 +0200 Message-ID: <55266885.6010905@sandisk.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Thomas Gleixner , Peter Zijlstra , To: "David S. Miller" Return-path: Received: from mail-bl2on0085.outbound.protection.outlook.com ([65.55.169.85]:5629 "EHLO na01-bl2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753694AbbDIM0u (ORCPT ); Thu, 9 Apr 2015 08:26:50 -0400 Sender: netdev-owner@vger.kernel.org List-ID: console_cont_flush(), which is called by console_unlock(), calls call_console_drivers() and hence also the netconsole function write_msg() with local interrupts disabled. This means that it is not allowed to call disable_irq() from inside a netpoll callback function. Hence eliminate the disable_irq() / enable_irq() pair from the e1000 netpoll function. This patch avoids that the e1000 networking driver triggers the following complaint: BUG: sleeping function called from invalid context at kernel/irq/manage.c:104 Call Trace: [] dump_stack+0x4c/0x65 [] ___might_sleep+0x175/0x230 [] __might_sleep+0x3a/0xa0 [] synchronize_irq+0x38/0xa0 [] disable_irq+0x20/0x30 [] e1000_netpoll+0x102/0x130 [e1000e] [] netpoll_poll_dev+0x72/0x350 [] netpoll_send_skb_on_dev+0x1b9/0x2b0 [] netpoll_send_udp+0x2c2/0x430 [] write_msg+0xcf/0x120 [netconsole] [] call_console_drivers.constprop.25+0xc2/0x250 [] console_unlock+0x328/0x4c0 [] vprintk_emit+0x2d0/0x570 [] vprintk_default+0x1f/0x30 [] printk+0x46/0x48 See also "[RFC PATCH net-next 00/11] net: remove disable_irq() from ->ndo_poll_controller" (http://thread.gmane.org/gmane.linux.network/342096). See also patch "sched/wait: Add might_sleep() checks" (kernel v3.19-rc1; commit e22b886a8a43). Reported-by: Sabrina Dubroca Signed-off-by: Bart Van Assche Cc: Thomas Gleixner Cc: David S. Miller Cc: Peter Zijlstra Cc: --- drivers/net/ethernet/intel/e1000/e1000.h | 5 +++++ drivers/net/ethernet/intel/e1000/e1000_main.c | 27 ++++++++++++++++++++++----- 2 files changed, 27 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000/e1000.h b/drivers/net/ethernet/intel/e1000/e1000.h index 6970710..d85d19f 100644 --- a/drivers/net/ethernet/intel/e1000/e1000.h +++ b/drivers/net/ethernet/intel/e1000/e1000.h @@ -323,6 +323,11 @@ struct e1000_adapter { struct delayed_work watchdog_task; struct delayed_work fifo_stall_task; struct delayed_work phy_info_task; + +#ifdef CONFIG_NET_POLL_CONTROLLER + /* Used to serialize e1000 interrupts and the e1000 netpoll callback. */ + spinlock_t netpoll_lock; +#endif }; enum e1000_state_t { diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c index 7f997d3..36870f8 100644 --- a/drivers/net/ethernet/intel/e1000/e1000_main.c +++ b/drivers/net/ethernet/intel/e1000/e1000_main.c @@ -1313,6 +1313,9 @@ static int e1000_sw_init(struct e1000_adapter *adapter) e1000_irq_disable(adapter); spin_lock_init(&adapter->stats_lock); +#ifdef CONFIG_NET_POLL_CONTROLLER + spin_lock_init(&adapter->netpoll_lock); +#endif set_bit(__E1000_DOWN, &adapter->flags); @@ -3751,10 +3754,8 @@ void e1000_update_stats(struct e1000_adapter *adapter) * @irq: interrupt number * @data: pointer to a network interface device structure **/ -static irqreturn_t e1000_intr(int irq, void *data) +static irqreturn_t __e1000_intr(int irq, struct e1000_adapter *adapter) { - struct net_device *netdev = data; - struct e1000_adapter *adapter = netdev_priv(netdev); struct e1000_hw *hw = &adapter->hw; u32 icr = er32(ICR); @@ -3796,6 +3797,24 @@ static irqreturn_t e1000_intr(int irq, void *data) return IRQ_HANDLED; } +static irqreturn_t e1000_intr(int irq, void *data) +{ + struct net_device *netdev = data; + struct e1000_adapter *adapter = netdev_priv(netdev); + irqreturn_t ret; +#ifdef CONFIG_NET_POLL_CONTROLLER + unsigned long flags; + + spin_lock_irqsave(&adapter->netpoll_lock, flags); + ret = __e1000_intr(irq, adapter); + spin_unlock_irqrestore(&adapter->netpoll_lock, flags); +#else + ret = __e1000_intr(irq, adapter); +#endif + + return ret; +} + /** * e1000_clean - NAPI Rx polling callback * @adapter: board private structure @@ -5220,9 +5239,7 @@ static void e1000_netpoll(struct net_device *netdev) { struct e1000_adapter *adapter = netdev_priv(netdev); - disable_irq(adapter->pdev->irq); e1000_intr(adapter->pdev->irq, netdev); - enable_irq(adapter->pdev->irq); } #endif -- 2.1.4