This is a note to let you know that I've just added the patch titled e1000: Do not perform reset in reset_task if we are already down to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: e1000-do-not-perform-reset-in-reset_task-if-we-are-a.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2d49710e061b782788374ec8b37942b74c594d55 Author: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx> Date: Fri Apr 17 09:35:31 2020 -0700 e1000: Do not perform reset in reset_task if we are already down [ Upstream commit 49ee3c2ab5234757bfb56a0b3a3cb422f427e3a3 ] 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. Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx> Tested-by: Maxim Zhukov <mussitantesmortem@xxxxxxxxx> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c index f93ed70709c65..a2ee28e487a6f 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);