[PATCH AUTOSEL for-4.9 40/53] ixgbe: handle close/suspend race with netif_device_detach/present

From: Levin, Alexander (Sasha Levin)
Date: Wed Nov 08 2017 - 16:13:39 EST


From: Emil Tantilov <emil.s.tantilov@xxxxxxxxx>

[ Upstream commit f7f37e7ff2b9b7eff7fbd035569cab35896869a3 ]

When an interface is part of a namespace it is possible that
ixgbe_close() may be called while __ixgbe_shutdown() 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 ixgbe_clear_interrupt_scheme()
in __ixgbe_shutdown() and check for netif_device_present()
to avoid clearing the interrupts second time in ixgbe_close();

Also extend the rtnl lock in ixgbe_resume() to netif_device_attach().

Signed-off-by: Emil Tantilov <emil.s.tantilov@xxxxxxxxx>
Tested-by: Andrew Bowers <andrewx.bowers@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 78173ca89ada..334eb96ecda3 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -6194,7 +6194,8 @@ int ixgbe_close(struct net_device *netdev)

ixgbe_ptp_stop(adapter);

- ixgbe_close_suspend(adapter);
+ if (netif_device_present(netdev))
+ ixgbe_close_suspend(adapter);

ixgbe_fdir_filter_exit(adapter);

@@ -6239,14 +6240,12 @@ static int ixgbe_resume(struct pci_dev *pdev)
if (!err && netif_running(netdev))
err = ixgbe_open(netdev);

- rtnl_unlock();

- if (err)
- return err;
-
- netif_device_attach(netdev);
+ if (!err)
+ netif_device_attach(netdev);
+ rtnl_unlock();

- return 0;
+ return err;
}
#endif /* CONFIG_PM */

@@ -6261,14 +6260,14 @@ static int __ixgbe_shutdown(struct pci_dev *pdev, bool *enable_wake)
int retval = 0;
#endif

+ rtnl_lock();
netif_device_detach(netdev);

- rtnl_lock();
if (netif_running(netdev))
ixgbe_close_suspend(adapter);
- rtnl_unlock();

ixgbe_clear_interrupt_scheme(adapter);
+ rtnl_unlock();

#ifdef CONFIG_PM
retval = pci_save_state(pdev);
--
2.11.0