• John Fastabend's avatar
    ixgbevf: make netif_napi_add and netif_napi_del symmetric · f4477702
    John Fastabend authored
    ixgbevf_alloc_q_vectors() calls netif_napi_add for each qvector
    where qvectors is determined by the number of msix vectors. This
    makes perfect sense.
    
    However on cleanup when ixgbevf_free_q_vectors() is called and
    for each qvector we should call netif_napi_del there is some
    extra logic to add a dependency on RX queues. This patch makes
    the add/del operations symmetric by removing the RX queues
    dependency.
    
    Without this if  free_netdev() is called we see the general
    protection fault below in netif_napi_del when list_del_init()
    is called.
    
    # addr2line -e ./vmlinux ffffffff8140810c
    net-next/include/linux/list.h:88
    
    general protection fault: 0000 [#1] SMP
    Modules linked in: bonding ixgbevf ixgbe(-) mdio libfc scsi_transport_fc scsi_tgt 8021q garp stp llc cpufreq_ondemand acpi_cpufreq freq_table mperf ipv6 uinput coretemp lpc_ich i2c_i801 shpchp hwmon i2c_core serio_raw crc32c_intel mfd_core joydev pcspkr microcode ioatdma igb dca pata_acpi ata_generic usb_storage pata_jmicron [last unloaded: bonding]
    CPU 10
    Pid: 4174, comm: rmmod Tainted: G        W    3.6.0-rc3jk-net-next+ #104 Supermicro X8DTN/X8DTN
    RIP: 0010:[<ffffffff8140810c>]  [<ffffffff8140810c>] netif_napi_del+0x24/0x87
    RSP: 0018:ffff88027f5e9b48  EFLAGS: 00010293
    RAX: ffff8806224b4768 RBX: ffff8806224b46e8 RCX: 6b6b6b6b6b6b6b6b
    RDX: 6b6b6b6b6b6b6b6b RSI: ffffffff810bf6c5 RDI: ffff8806224b46e8
    RBP: ffff88027f5e9b58 R08: ffff88033200b180 R09: ffff88027f5e98a8
    R10: ffff88033320b000 R11: ffff88027f5e9ae8 R12: 6b6b6b6b6b6b6aeb
    R13: ffff8806221d11c0 R14: 0000000000000000 R15: ffff88027f5e9cf8
    FS:  00007f5e58b9b700(0000) GS:ffff880333200000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
    CR2: 00000000010ef2b8 CR3: 0000000281fff000 CR4: 00000000000007e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
    Process rmmod (pid: 4174, threadinfo ffff88027f5e8000, task ffff88032f888000)
    Stack:
     ffff8806221d1160 6b6b6b6b6b6b6aeb ffff88027f5e9b88 ffffffff81408e46
     ffff8806221d1160 ffff8806221d1160 ffff8806221d1ae0 ffff8806221d5668
     ffff88027f5e9bb8 ffffffffa009153c ffffffffa0092a30 ffff8806221d5700
    Call Trace:
     [<ffffffff81408e46>] free_netdev+0x64/0xd7
     [<ffffffffa009153c>] ixgbevf_remove+0xa6/0xbc [ixgbevf]
     [<ffffffff8127a7a1>] pci_device_remove+0x2d/0x51
     [<ffffffff8131f503>] __device_release_driver+0x6c/0xc2
     [<ffffffff8131f640>] device_release_driver+0x25/0x32
     [<ffffffff8131e821>] bus_remove_device+0x148/0x15d
     [<ffffffff8131cb6b>] device_del+0x130/0x1a4
     [<ffffffff8131cc2a>] device_unregister+0x4b/0x57
     [<ffffffff81275c27>] pci_stop_bus_device+0x63/0x85
     [...]
    Signed-off-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
    Acked-by: default avatarGreg Rose <gregory.v.rose@intel.com>
    Acked-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
    Tested-by: default avatarSibai Li <sibai.li@intel.com>
    Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
    f4477702
ixgbevf_main.c 94.3 KB