Patch "ixgbe: handle close/suspend race with netif_device_detach/present" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    ixgbe: handle close/suspend race with netif_device_detach/present

to the 4.4-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:
     ixgbe-handle-close-suspend-race-with-netif_device_detach-present.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Sun Nov 19 12:02:55 CET 2017
From: Emil Tantilov <emil.s.tantilov@intel.com>
Date: Fri, 11 Nov 2016 10:07:47 -0800
Subject: ixgbe: handle close/suspend race with netif_device_detach/present

From: Emil Tantilov <emil.s.tantilov@intel.com>


[ 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@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c |   17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -5878,7 +5878,8 @@ static int ixgbe_close(struct net_device
 
 	ixgbe_ptp_stop(adapter);
 
-	ixgbe_close_suspend(adapter);
+	if (netif_device_present(netdev))
+		ixgbe_close_suspend(adapter);
 
 	ixgbe_fdir_filter_exit(adapter);
 
@@ -5923,14 +5924,12 @@ static int ixgbe_resume(struct pci_dev *
 	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 */
 
@@ -5945,14 +5944,14 @@ static int __ixgbe_shutdown(struct pci_d
 	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);


Patches currently in stable-queue which might be from emil.s.tantilov@intel.com are

queue-4.4/ixgbe-handle-close-suspend-race-with-netif_device_detach-present.patch
queue-4.4/ixgbe-do-not-disable-fec-from-the-driver.patch
queue-4.4/ixgbe-fix-aer-error-handling.patch
queue-4.4/ixgbe-add-mask-for-64-rss-queues.patch