From: Alexander Duyck alexander.h.duyck@linux.intel.com

We are seeing a deadlock in e1000 down when NAPI is being disabled. Looking over the kernel function trace of the system it appears that the interface is being closed and then a reset is hitting which deadlocks the interface as the NAPI interface is already disabled.

To prevent this from happening I am disabling the reset task when __E1000_DOWN is already set. In addition code has been added so that we set the __E1000_DOWN while holding the __E1000_RESET flag in e1000_close in order to guarantee that the reset task will not run after we have started the close call.

CC: stable stable@vger.kernel.org Signed-off-by: Alexander Duyck alexander.h.duyck@linux.intel.com Tested-by: Maxim Zhukov mussitantesmortem@gmail.com Signed-off-by: Jeff Kirsher jeffrey.t.kirsher@intel.com --- drivers/net/ethernet/intel/e1000/e1000_main.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c index 05bc6e216bca..d9fa4600f745 100644 --- a/drivers/net/ethernet/intel/e1000/e1000_main.c +++ b/drivers/net/ethernet/intel/e1000/e1000_main.c @@ -542,8 +542,13 @@ void e1000_reinit_locked(struct e1000_adapter *adapter) WARN_ON(in_interrupt()); while (test_and_set_bit(__E1000_RESETTING, &adapter->flags)) msleep(1); - e1000_down(adapter); - e1000_up(adapter); + + /* only run the task if not already down */ + if (!test_bit(__E1000_DOWN, &adapter->flags)) { + e1000_down(adapter); + e1000_up(adapter); + } + clear_bit(__E1000_RESETTING, &adapter->flags); }

@@ -1433,10 +1438,15 @@ int e1000_close(struct net_device *netdev) struct e1000_hw *hw = &adapter->hw; int count = E1000_CHECK_RESET_COUNT;

- while (test_bit(__E1000_RESETTING, &adapter->flags) && count--) + while (test_and_set_bit(__E1000_RESETTING, &adapter->flags) && count--) usleep_range(10000, 20000);

- WARN_ON(test_bit(__E1000_RESETTING, &adapter->flags)); + WARN_ON(count < 0); + + /* signal that we're down so that the reset task will no longer run */ + set_bit(__E1000_DOWN, &adapter->flags); + clear_bit(__E1000_RESETTING, &adapter->flags); + e1000_down(adapter); e1000_power_down_phy(adapter); e1000_free_irq(adapter);