# Kernel panic when using comconsole



## NE (Aug 4, 2014)

Hi,
When activating comconsole on an IBM host (IBM xseries 336 hardware), the boot fails when activating the com port using console="comconsole,vidconsole" in /boot/loader.conf.
The stacktrace:

```
[...]
bge0: <Broadcom NetXtreme Gigabit Ethernet Controller, ASIC rev. 0x004101> mem 0xdcff0000-0xdcffffff irq 16 at device 0.0 on pci6
bge0: CHIP ID 0x00004101; ASIC REV 0x04; CHIP REV 0x41; PCI-E
miibus0: <MII bus> on bge0
ukphy0: <Generic IEEE 802.3u media interface> PHY 1 on miibus0
ukphy0:  no media present
ifmedia_set: no match for 0x0/0xfffffff
panic: ifmedia_set
cpuid = 0
KDB: stack backtrace:
#0 0xc0af6f12 at kdb_backtrace+0x52
#1 0xc0abce21 at panic+0x121
#2 0xc0b86744 at ifmedia_set+0x64
#3 0xc0794dc1 at miibus_mediainit+0x91
#4 0xc07965b3 at mii_phy_dev_attach+0x273
#5 0xc079d8a5 at ukphy_attach+0x35
#6 0xc0aede68 at device_attach+0x3d8
#7 0xc0aeeeeb at bus_generic_attach+0x2b
#8 0xc0794780 at miibus_attach+0xb0
#9 0xc0aede68 at device_attach+0x3d8
#10 0xc0aeeeeb at bus_generic_attach+0x2b
#11 0xc0794353 at mii_attach+0x4a3
#12 0xc0670912 at bge_attach+0x43e2
#13 0xc0aede68 at device_attach+0x3d8
#14 0xc0aeeeeb at bus_generic_attach+0x2b
#15 0xc0540dba at acpi_pci_attach+0x19a
#16 0xc0aede68 at device_attach+0x3d8
#17 0xc0aeeeeb at bus_generic_attach+0x2b
Uptime: 1s
```

When disabling the comconsole (ie using only vidconsole, the boot succeeds nicely:

```
[...]
bge0: <Broadcom NetXtreme Gigabit Ethernet Controller, ASIC rev. 0x004101> mem 0xdcff0000-0xdcffffff irq 16 at device 0.0 on pci6
bge0: CHIP ID 0x00004101; ASIC REV 0x04; CHIP REV 0x41; PCI-E
miibus0: <MII bus> on bge0
ukphy0: <Generic IEEE 802.3u media interface> PHY 1 on miibus0
ukphy0:  none, 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseT, 1000baseT-master, 1000baseT-FDX, 1000baseT-FDX-master, auto, auto-flow
bge0: Ethernet address: 00:14:5e:80:83:32
pcib6: <ACPI PCI-PCI bridge> at device 7.0 on pci0
pci7: <ACPI PCI bus> on pcib6
bge1: <Broadcom NetXtreme Gigabit Ethernet Controller, ASIC rev. 0x004101> mem 0xdaff0000-0xdaffffff irq 16 at device 0.0 on pci7
bge1: CHIP ID 0x00004101; ASIC REV 0x04; CHIP REV 0x41; PCI-E
miibus1: <MII bus> on bge1
brgphy0: <BCM5750 1000BASE-T media interface> PHY 1 on miibus1
brgphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseT, 1000baseT-master, 1000baseT-FDX, 1000baseT-FDX-master, auto, auto-flow
bge1: Ethernet address: 00:14:5e:80:83:33
[...]
```

So activating the comconsole module makes the network interfaces init fail and leads to kernel panic.
Any idea on how to fix this ?
Thanks


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## NE (Aug 19, 2014)

FYI, this does happen with 10.0-RELEASE and 9.3-RELEASE but won't with 9.1-RELEASE.


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