From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Subject: [net 3/5] e1000e: prevent oops when adapter is being closed and reset simultaneously Date: Tue, 3 Apr 2012 15:18:07 -0700 Message-ID: <1333491489-29933-4-git-send-email-jeffrey.t.kirsher@intel.com> References: <1333491489-29933-1-git-send-email-jeffrey.t.kirsher@intel.com> Cc: Bruce Allan , netdev@vger.kernel.org, gospo@redhat.com, sassmann@redhat.com, Jeff Kirsher To: davem@davemloft.net Return-path: Received: from mga02.intel.com ([134.134.136.20]:49249 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753502Ab2DCWSN (ORCPT ); Tue, 3 Apr 2012 18:18:13 -0400 In-Reply-To: <1333491489-29933-1-git-send-email-jeffrey.t.kirsher@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Bruce Allan When the adapter is closed while it is simultaneously going through a reset, it can cause a null-pointer dereference when the two different code paths simultaneously cleanup up the Tx/Rx resources. Signed-off-by: Bruce Allan Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/e1000e/e1000.h | 6 ++++++ drivers/net/ethernet/intel/e1000e/netdev.c | 9 +++++++++ 2 files changed, 15 insertions(+), 0 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/e1000.h b/drivers/net/ethernet/intel/e1000e/e1000.h index 86cdd47..b83897f 100644 --- a/drivers/net/ethernet/intel/e1000e/e1000.h +++ b/drivers/net/ethernet/intel/e1000e/e1000.h @@ -161,6 +161,12 @@ struct e1000_info; /* Time to wait before putting the device into D3 if there's no link (in ms). */ #define LINK_TIMEOUT 100 +/* + * Count for polling __E1000_RESET condition every 10-20msec. + * Experimentation has shown the reset can take approximately 210msec. + */ +#define E1000_CHECK_RESET_COUNT 25 + #define DEFAULT_RDTR 0 #define DEFAULT_RADV 8 #define BURST_RDTR 0x20 diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 2c38a65..6878601 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -3968,6 +3968,10 @@ static int e1000_close(struct net_device *netdev) { struct e1000_adapter *adapter = netdev_priv(netdev); struct pci_dev *pdev = adapter->pdev; + int count = E1000_CHECK_RESET_COUNT; + + while (test_bit(__E1000_RESETTING, &adapter->state) && count--) + usleep_range(10000, 20000); WARN_ON(test_bit(__E1000_RESETTING, &adapter->state)); @@ -5472,6 +5476,11 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool *enable_wake, netif_device_detach(netdev); if (netif_running(netdev)) { + int count = E1000_CHECK_RESET_COUNT; + + while (test_bit(__E1000_RESETTING, &adapter->state) && count--) + usleep_range(10000, 20000); + WARN_ON(test_bit(__E1000_RESETTING, &adapter->state)); e1000e_down(adapter); e1000_free_irq(adapter); -- 1.7.7.6