[PATCH AUTOSEL 4.9 77/90] e1000: Do not perform reset in reset_task if we are already down
From: Sasha Levin <sashal@kernel.org>
Date: 2020-09-18 02:25:00
Also in:
intel-wired-lan, lkml, stable
Subsystem:
intel ethernet drivers, networking drivers, the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Alexander Duyck <redacted> [ 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 <redacted> Tested-by: Maxim Zhukov <redacted> Signed-off-by: Jeff Kirsher <redacted> Signed-off-by: Sasha Levin <sashal@kernel.org> --- 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 3b16ee0de246e..c30792b761ee3 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c@@ -568,8 +568,13 @@ 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); }
@@ -1456,10 +1461,15 @@ 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);
--
2.25.1