Qinhuibin reported a kernel panic when he do some operation about vlan.
https://lkml.org/lkml/2011/11/6/218
The operation is as below:
ifconfig eth2 up
modprobe bonding
modprobe 8021q
ifconfig bond0 up
ifenslave bond0 eth2
vconfig add eth2 3300
vconfig add bond0 33
vconfig rem eth2.3300
the panic stack is as below:
[<ffffffffa002f1c9>] panic_event+0x49/0x70 [ipmi_msghandler]
[<ffffffff80378917>] notifier_call_chain+0x37/0x70
[<ffffffff80372122>] panic+0xa2/0x195
[<ffffffff80376ed8>] oops_end+0xd8/0x140
[<ffffffff8001bea7>] no_context+0xf7/0x280
[<ffffffff8001c1a5>] __bad_area_nosemaphore+0x175/0x250
[<ffffffff80376318>] page_fault+0x28/0x30
[<ffffffffa039dabd>] igb_vlan_rx_kill_vid+0x4d/0x100 [igb]
[<ffffffffa044045f>] bond_vlan_rx_kill_vid+0x9f/0x290 [bonding]
[<ffffffffa047e636>] unregister_vlan_dev+0x136/0x180 [8021q]
[<ffffffffa047ed20>] vlan_ioctl_handler+0x170/0x3f0 [8021q]
[<ffffffff802c1d3f>] sock_ioctl+0x21f/0x280
[<ffffffff800e6d7f>] vfs_ioctl+0x2f/0xb0
[<ffffffff800e726b>] do_vfs_ioctl+0x3cb/0x5a0
[<ffffffff800e74e1>] sys_ioctl+0xa1/0xb0
[<ffffffff80007388>] system_call_fastpath+0x16/0x1b
[<00007f108a2b8bd7>] 0x7f108a2b8bd7
And the nic is as below:
[root@localhost ~]# ethtool -i eth2
driver: igb
version: 3.0.6-k2
firmware-version: 1.2-1
bus-info: 0000:04:00.0
kernel versionï
2.6.32.12-0.7 also happen in 2.6.32-131
For kernel 2.6.32, the reason of this bug is that when we do "vconfig add bond0 33",
adapter->vlgrp is overwritten in igb_vlan_rx_register. So when we do "vconfig rem
eth2.3300", it can't find the correct vlgrp.
And this bug is avoided by vlan cleanup patchset from Jiri Pirko
<jpirko@xxxxxxxxxx>, especially commit b2cb09b1a772(igb: do vlan cleanup).
But it is not a correct operation to creat a vlan interface on eth2
when it have been enslaved by bond0, so this patch is to return error
when the real dev is already enslaved.