Using the x86_64 kernel.

I suspect this was triggered because of turning off hardware checking (re Bug #7579)

using: ethtool -K eth0 rx off tx off

NETDEV WATCHDOG: eth0: transmit timed out
sky2 eth0: tx timeout
sky2 eth0: transmit ring 308 .. 267 report=308 done=308
sky2 hardware hung? flushing
BUG: spinlock recursion on CPU#0, swapper/0
 lock: ffff81007db3ba80, .magic: dead4ead, .owner: swapper/0, .owner_cpu: 0

Call Trace:
 [<ffffffff80268752>] show_trace+0x34/0x47
 [<ffffffff80268777>] dump_stack+0x12/0x17
 [<ffffffff8020771c>] _raw_spin_lock+0x40/0xf2
 [<ffffffff8819af6a>] :sky2:sky2_tx_clean+0x1e/0x51
 [<ffffffff8819d1aa>] :sky2:sky2_tx_timeout+0x165/0x194
 [<ffffffff8023e057>] dev_watchdog+0x7b/0xc2
 [<ffffffff802913aa>] run_timer_softirq+0x13b/0x1b5
 [<ffffffff80211924>] __do_softirq+0x55/0xc3
 [<ffffffff8025c24c>] call_softirq+0x1c/0x30
 [<ffffffff802697bc>] do_softirq+0x2c/0x7d
 [<ffffffff80273921>] smp_apic_timer_interrupt+0x56/0x68
 [<ffffffff8025bcf6>] apic_timer_interrupt+0x66/0x70
 [<ffffffff80267ead>] mwait_idle_with_hints+0x44/0x45
 [<ffffffff802547f9>] mwait_idle+0xc/0x20
 [<ffffffff80246b8b>] cpu_idle+0x8b/0xae
 [<ffffffff80895697>] start_kernel+0x22a/0x22f
 [<ffffffff8089515c>] _sinittext+0x15c/0x160

BUG: soft lockup detected on CPU#0!

Call Trace:
 [<ffffffff80268752>] show_trace+0x34/0x47
 [<ffffffff80268777>] dump_stack+0x12/0x17
 [<ffffffff802b3767>] softlockup_tick+0xdb/0xf6
 [<ffffffff80291977>] update_process_times+0x42/0x68
 [<ffffffff8027323c>] smp_local_timer_interrupt+0x34/0x55
 [<ffffffff8027391c>] smp_apic_timer_interrupt+0x51/0x68
 [<ffffffff8025bcf6>] apic_timer_interrupt+0x66/0x70
 [<ffffffff8020c14c>] __delay+0x2/0x10
 [<ffffffff8020776a>] _raw_spin_lock+0x8e/0xf2
 [<ffffffff8819af6a>] :sky2:sky2_tx_clean+0x1e/0x51
 [<ffffffff8819d1aa>] :sky2:sky2_tx_timeout+0x165/0x194
 [<ffffffff8023e057>] dev_watchdog+0x7b/0xc2
 [<ffffffff802913aa>] run_timer_softirq+0x13b/0x1b5
 [<ffffffff80211924>] __do_softirq+0x55/0xc3
 [<ffffffff8025c24c>] call_softirq+0x1c/0x30
 [<ffffffff802697bc>] do_softirq+0x2c/0x7d
 [<ffffffff80273921>] smp_apic_timer_interrupt+0x56/0x68
 [<ffffffff8025bcf6>] apic_timer_interrupt+0x66/0x70
 [<ffffffff80267ead>] mwait_idle_with_hints+0x44/0x45
 [<ffffffff802547f9>] mwait_idle+0xc/0x20
 [<ffffffff80246b8b>] cpu_idle+0x8b/0xae
 [<ffffffff80895697>] start_kernel+0x22a/0x22f
 [<ffffffff8089515c>] _sinittext+0x15c/0x160

BUG: soft lockup detected on CPU#0!

Call Trace:
 [<ffffffff80268752>] show_trace+0x34/0x47
 [<ffffffff80268777>] dump_stack+0x12/0x17
 [<ffffffff802b3767>] softlockup_tick+0xdb/0xf6
 [<ffffffff80291977>] update_process_times+0x42/0x68
 [<ffffffff8027323c>] smp_local_timer_interrupt+0x34/0x55
 [<ffffffff8027391c>] smp_apic_timer_interrupt+0x51/0x68
 [<ffffffff8025bcf6>] apic_timer_interrupt+0x66/0x70
 [<ffffffff8020c150>] __delay+0x6/0x10
 [<ffffffff8020776a>] _raw_spin_lock+0x8e/0xf2
 [<ffffffff8819af6a>] :sky2:sky2_tx_clean+0x1e/0x51
 [<ffffffff8819d1aa>] :sky2:sky2_tx_timeout+0x165/0x194
 [<ffffffff8023e057>] dev_watchdog+0x7b/0xc2
 [<ffffffff802913aa>] run_timer_softirq+0x13b/0x1b5
 [<ffffffff80211924>] __do_softirq+0x55/0xc3
 [<ffffffff8025c24c>] call_softirq+0x1c/0x30
 [<ffffffff802697bc>] do_softirq+0x2c/0x7d
 [<ffffffff80273921>] smp_apic_timer_interrupt+0x56/0x68
 [<ffffffff8025bcf6>] apic_timer_interrupt+0x66/0x70
 [<ffffffff80267ead>] mwait_idle_with_hints+0x44/0x45
 [<ffffffff802547f9>] mwait_idle+0xc/0x20
 [<ffffffff80246b8b>] cpu_idle+0x8b/0xae
 [<ffffffff80895697>] start_kernel+0x22a/0x22f
 [<ffffffff8089515c>] _sinittext+0x15c/0x160
....
lspci -vv
03:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8062 PCI-E IPMI
Gigabit Ethernet Controller (rev 14)
        Subsystem: ASUSTeK Computer Inc. Unknown device 81da
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
Stepping- SERR- FastB2B-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort-
<MAbort- >SERR- <PERR-
        Latency: 0, Cache Line Size: 16 bytes
        Interrupt: pin A routed to IRQ 8411
        Region 0: Memory at f97fc000 (64-bit, non-prefetchable) [size=16K]
        Region 2: I/O ports at b800 [size=256]
        Expansion ROM at f97c0000 [disabled] [size=128K]
        Capabilities: [48] Power Management version 2
                Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA
PME(D0+,D1+,D2+,D3hot+,D3cold+)
                Status: D0 PME-Enable- DSel=0 DScale=1 PME-
        Capabilities: [50] Vital Product Data
        Capabilities: [5c] Message Signalled Interrupts: 64bit+ Queue=0/1 Enable+
                Address: 00000000fee01000  Data: 40b1
        Capabilities: [e0] Express Legacy Endpoint IRQ 0
                Device: Supported: MaxPayload 128 bytes, PhantFunc 0, ExtTag-
                Device: Latency L0s unlimited, L1 unlimited
                Device: AtnBtn- AtnInd- PwrInd-
                Device: Errors: Correctable- Non-Fatal- Fatal- Unsupported-
                Device: RlxdOrd- ExtTag- PhantFunc- AuxPwr+ NoSnoop-
                Device: MaxPayload 128 bytes, MaxReadReq 512 bytes
                Link: Supported Speed 2.5Gb/s, Width x4, ASPM L0s, Port 0
                Link: Latency L0s <256ns, L1 unlimited
                Link: ASPM Disabled RCB 128 bytes CommClk+ ExtSynch-
                Link: Speed 2.5Gb/s, Width x1
[root@emerald-x64 ~]# cat /proc/interrupts 
           CPU0       CPU1       
...
8411:         37       2913   PCI-MSI-edge      eth0


Phil
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