ixgbevf: Fix panic when loading driver

This patch addresses a kernel panic seen when setting up the interface.
Specifically we see a NULL pointer dereference on the Tx descriptor cleanup
path when enabling interrupts.  This change corrects that so it cannot
occur.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index 8b304a43a22d..41e32257a4e8 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -201,6 +201,9 @@ static bool ixgbevf_clean_tx_irq(struct ixgbevf_adapter *adapter,
         unsigned int i, eop, count = 0;
         unsigned int total_bytes = 0, total_packets = 0;
 
+        if (test_bit(__IXGBEVF_DOWN, &adapter->state))
+                return true;
+
         i = tx_ring->next_to_clean;
         eop = tx_ring->tx_buffer_info[i].next_to_watch;
         eop_desc = IXGBE_TX_DESC_ADV(*tx_ring, eop);