[src/trunk]: src/sys/dev/pci/ixgbe Fix race in ixgbe_detach() to prevent pani...

[msaitoh <msaitoh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/ce1b31241eb4
branches:  trunk
changeset: 937725:ce1b31241eb4
user:      msaitoh <msaitoh%NetBSD.org@localhost>
date:      Mon Aug 24 18:21:59 2020 +0000

description:
Fix race in ixgbe_detach() to prevent panic on shutdown.

diffstat:

 sys/dev/pci/ixgbe/ixgbe.c |  34 ++++++++++++++++++++--------------
 1 files changed, 20 insertions(+), 14 deletions(-)

diffs (62 lines):

diff -r 262577f2aed2 -r ce1b31241eb4 sys/dev/pci/ixgbe/ixgbe.c
--- a/sys/dev/pci/ixgbe/ixgbe.c Mon Aug 24 18:18:51 2020 +0000
+++ b/sys/dev/pci/ixgbe/ixgbe.c Mon Aug 24 18:21:59 2020 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: ixgbe.c,v 1.240 2020/08/24 18:16:04 msaitoh Exp $ */
+/* $NetBSD: ixgbe.c,v 1.241 2020/08/24 18:21:59 msaitoh Exp $ */
 
 /******************************************************************************
 
@@ -3558,13 +3558,6 @@
                return (EBUSY);
        }
 
-       /*
-        * Stop the interface. ixgbe_setup_low_power_mode() calls ixgbe_stop(),
-        * so it's not required to call ixgbe_stop() directly.
-        */
-       IXGBE_CORE_LOCK(adapter);
-       ixgbe_setup_low_power_mode(adapter);
-       IXGBE_CORE_UNLOCK(adapter);
 #if NVLAN > 0
        /* Make sure VLANs are not using driver */
        if (!VLAN_ATTACHED(&adapter->osdep.ec))
@@ -3577,6 +3570,25 @@
        }
 #endif
 
+       /*
+        * Stop the interface. ixgbe_setup_low_power_mode() calls ixgbe_stop(),
+        * so it's not required to call ixgbe_stop() directly.
+        */
+       IXGBE_CORE_LOCK(adapter);
+       ixgbe_setup_low_power_mode(adapter);
+       IXGBE_CORE_UNLOCK(adapter);
+
+       callout_halt(&adapter->timer, NULL);
+       if (adapter->feat_en & IXGBE_FEATURE_RECOVERY_MODE) {
+               callout_stop(&adapter->recovery_mode_timer);
+               callout_halt(&adapter->recovery_mode_timer, NULL);
+       }
+
+       workqueue_wait(adapter->admin_wq, &adapter->admin_wc);
+       atomic_store_relaxed(&adapter->admin_pending, 0);
+       workqueue_wait(adapter->timer_wq, &adapter->timer_wc);
+       atomic_store_relaxed(&adapter->timer_pending, 0);
+
        pmf_device_deregister(dev);
 
        ether_ifdetach(adapter->ifp);
@@ -3588,12 +3600,6 @@
        ctrl_ext &= ~IXGBE_CTRL_EXT_DRV_LOAD;
        IXGBE_WRITE_REG(&adapter->hw, IXGBE_CTRL_EXT, ctrl_ext);
 
-       callout_halt(&adapter->timer, NULL);
-       if (adapter->feat_en & IXGBE_FEATURE_RECOVERY_MODE) {
-               callout_stop(&adapter->recovery_mode_timer);
-               callout_halt(&adapter->recovery_mode_timer, NULL);
-       }
-
        if (adapter->feat_en & IXGBE_FEATURE_NETMAP)
                netmap_detach(adapter->ifp);