If the netdev is already in NETREG_UNREGISTERING/_UNREGISTERED state, do not
update the real num tx queues. netdev_queue_update_kobjects() is already
called via remove_queue_kobjects() at NETREG_UNREGISTERING time. So, when
upper layer driver, e.g., FCoE protocol stack is monitoring the netdev
event of NETDEV_UNREGISTER and calls back to LLD ndo_fcoe_disable() to remove
extra queues allocated for FCoE, the associated txq sysfs kobjects are already
removed, and trying to update the real num queues would cause something like
below:
...
PID: 25138 TASK: ffff88021e64c440 CPU: 3 COMMAND: "kworker/3:3"
#0 [ffff88021f007760] machine_kexec at ffffffff810226d9
#1 [ffff88021f0077d0] crash_kexec at ffffffff81089d2d
#2 [ffff88021f0078a0] oops_end at ffffffff813bca78
#3 [ffff88021f0078d0] no_context at ffffffff81029e72
#4 [ffff88021f007920] __bad_area_nosemaphore at ffffffff8102a155
#5 [ffff88021f0079f0] bad_area_nosemaphore at ffffffff8102a23e
#6 [ffff88021f007a00] do_page_fault at ffffffff813bf32e
#7 [ffff88021f007b10] page_fault at ffffffff813bc045
[exception RIP: sysfs_find_dirent+17]
RIP: ffffffff81178611 RSP: ffff88021f007bc0 RFLAGS: 00010246
RAX: ffff88021e64c440 RBX: ffffffff8156cc63 RCX: 0000000000000004
RDX: ffffffff8156cc63 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88021f007be0 R8: 0000000000000004 R9: 0000000000000008
R10: ffffffff816fed00 R11: 0000000000000004 R12: 0000000000000000
R13: ffffffff8156cc63 R14: 0000000000000000 R15: ffff8802222a0000
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#8 [ffff88021f007be8] sysfs_get_dirent at ffffffff81178c07
#9 [ffff88021f007c18] sysfs_remove_group at ffffffff8117ac27
#10 [ffff88021f007c48] netdev_queue_update_kobjects at ffffffff813178f9
#11 [ffff88021f007c88] netif_set_real_num_tx_queues at ffffffff81303e38
#12 [ffff88021f007cc8] ixgbe_set_num_queues at ffffffffa0249763 [ixgbe]
#13 [ffff88021f007cf8] ixgbe_init_interrupt_scheme at ffffffffa024ea89 [ixgbe]
#14 [ffff88021f007d48] ixgbe_fcoe_disable at ffffffffa0267113 [ixgbe]
#15 [ffff88021f007d68] vlan_dev_fcoe_disable at ffffffffa014fef5 [8021q]
#16 [ffff88021f007d78] fcoe_interface_cleanup at ffffffffa02b7dfd [fcoe]
#17 [ffff88021f007df8] fcoe_destroy_work at ffffffffa02b7f08 [fcoe]
#18 [ffff88021f007e18] process_one_work at ffffffff8105d7ca
#19 [ffff88021f007e68] worker_thread at ffffffff81060513
#20 [ffff88021f007ee8] kthread at ffffffff810648b6
#21 [ffff88021f007f48] kernel_thread_helper at ffffffff813c40f4
Signed-off-by: Yi Zou <yi.zou@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Tested-by: Stephen Ko <stephen.s.ko@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
9d837ea2b7