[net-next 09/21] ixgbevf: handle race between close and suspend on shutdown

[Jeff Kirsher]

From: Emil Tantilov <emil.s.tanti...@intel.com>

When an interface is part of a namespace it is possible that
ixgbevf_close() may be called while ixgbevf_suspend() is running
which ends up in a double free WARN and/or a BUG in free_msi_irqs()

To handle this situation we extend the rtnl_lock() to protect the
call to netif_device_detach() and check for !netif_device_present()
to avoid entering close while in suspend.

Also added rtnl locks to ixgbevf_queue_reset_subtask().

CC: Alexander Duyck <alexander.h.du...@intel.com>
Signed-off-by: Emil Tantilov <emil.s.tanti...@intel.com>
Tested-by: Andrew Bowers <andrewx.bow...@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirs...@intel.com>
---
 drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c 
b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index 6d4bef5..8574f21 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -3242,6 +3242,9 @@ int ixgbevf_close(struct net_device *netdev)
 {
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);
 
+       if (!netif_device_present(netdev))
+               return 0;
+
        ixgbevf_down(adapter);
        ixgbevf_free_irq(adapter);
 
@@ -3268,6 +3271,8 @@ static void ixgbevf_queue_reset_subtask(struct 
ixgbevf_adapter *adapter)
         * match packet buffer alignment. Unfortunately, the
         * hardware is not flexible enough to do this dynamically.
         */
+       rtnl_lock();
+
        if (netif_running(dev))
                ixgbevf_close(dev);
 
@@ -3276,6 +3281,8 @@ static void ixgbevf_queue_reset_subtask(struct 
ixgbevf_adapter *adapter)
 
        if (netif_running(dev))
                ixgbevf_open(dev);
+
+       rtnl_unlock();
 }
 
 static void ixgbevf_tx_ctxtdesc(struct ixgbevf_ring *tx_ring,
@@ -3796,17 +3803,17 @@ static int ixgbevf_suspend(struct pci_dev *pdev, 
pm_message_t state)
        int retval = 0;
 #endif
 
+       rtnl_lock();
        netif_device_detach(netdev);
 
        if (netif_running(netdev)) {
-               rtnl_lock();
                ixgbevf_down(adapter);
                ixgbevf_free_irq(adapter);
                ixgbevf_free_all_tx_resources(adapter);
                ixgbevf_free_all_rx_resources(adapter);
                ixgbevf_clear_interrupt_scheme(adapter);
-               rtnl_unlock();
        }
+       rtnl_unlock();
 
 #ifdef CONFIG_PM
        retval = pci_save_state(pdev);
-- 
2.9.3