Re: brcmfmac: kernel panic in brcmf_cfg80211_del_key

[Arend van Spriel <arend@broadcom.com>]

On 01/23/15 15:21, Arend van Spriel wrote:
> On 01/23/15 13:31, Jörg Krause wrote:
>> Hi all,
>>
>> I'm running an wireless device with Linux kernel 3.18.3 and the brcmfmac
>> driver. When connection the device to my network, I see from time to
>> time these messages in the kernel log:
>>
>> [ 899.624759] brcmfmac: brcmf_cfg80211_del_key: invalid key index (4)
>> [ 899.649874] brcmfmac: brcmf_cfg80211_del_key: invalid key index (5)
>> [ 899.678066] cfg80211: Calling CRDA to update world regulatory domain
>>
>> I'm not sure about the meaning of the 'invalid key index' messages and
>> if it may cause some trouble. However the system is running fine.
>
> Basically, wpa_supplicant does key deletion for index 0 to 5, but
> brcmfmac only has 4 keys (0 to 3) hence the message. This is not an issue.
>
>> Now I had a test case with two wireless devices having the same hostname
>> and MAC address in the same network.
>
> What? Why is this a test case. That is fundamentally wrong and asking
> for trouble.
>
>> The first wireless devices connects to the network and starts receiving
>> an audio stream via UDP. Another device with same hostname and MAC is
>> started after this and repeatedly reboots after 30 seconds.
>>
>> The first device gets disconnected after the second device connects to
>> the network. The device is running with the network tools tools
>> wpa_supplicant, a wpa_action script, udhcpc, avahi, and crda. The device
>> tries to reconnect to the network. It successfully connects, but
>> authentification fails. This step produces a lot of the kernel messages
>> from above.
>>
>> Okay, nothing wrong until here I think. But after some time the brcmfmac
>> driver is dying:
>>
>> [ 901.799454] ------------[ cut here ]------------
>> [ 901.804332] WARNING: CPU: 0 PID: 104 at
>> drivers/net/wireless/brcm80211/brcmfmac/dhd_linux.c:1076
>> brcmf_netdev_wait_pend8021x+0xe0/0xf4 [brcmfmac]()
>> [ 901.866565] Modules linked in:
>> [ 901.907705] brcmfmac brcmutil
>> [ 901.909298] CPU: 0 PID: 104 Comm: wpa_supplicant Not tainted 3.18.3
>> #1
>> [ 901.959287] [<c000de40>] (unwind_backtrace) from [<c000c1f4>]
>> (show_stack+0x10/0x14)
>> [ 901.993628] [<c000c1f4>] (show_stack) from [<c0016400>]
>> (warn_slowpath_common+0x68/0x88)
>> [ 902.016243] [<c0016400>] (warn_slowpath_common) from [<c00164bc>]
>> (warn_slowpath_null+0x1c/0x24)
>> [ 902.040249] [<c00164bc>] (warn_slowpath_null) from [<bf016304>]
>> (brcmf_netdev_wait_pend8021x+0xe0/0xf4 [brcmfmac])
>> [ 902.067408] [<bf016304>] (brcmf_netdev_wait_pend8021x [brcmfmac])
>> from [<bf0061d8>] (brcmf_cfg80211_get_key+0x1a8/0x374 [brcmfmac])
>> [ 902.098434] [<bf0061d8>] (brcmf_cfg80211_get_key [brcmfmac]) from
>> [<bf00770c>] (brcmf_cfg80211_del_key+0x1d8/0x2e0 [brcmfmac])
>> [ 902.164527] [<bf00770c>] (brcmf_cfg80211_del_key [brcmfmac]) from
>> [<bf0078ec>] (brcmf_cfg80211_add_key+0xd8/0x248 [brcmfmac])
>> [ 902.213096] [<bf0078ec>] (brcmf_cfg80211_add_key [brcmfmac]) from
>> [<c037f368>] (nl80211_new_key+0x108/0x144)
>> [ 902.253581] [<c037f368>] (nl80211_new_key) from [<c02ccb98>]
>> (genl_rcv_msg+0x22c/0x39c)
>> [ 902.290997] [<c02ccb98>] (genl_rcv_msg) from [<c02cc12c>]
>> (netlink_rcv_skb+0xb4/0xd8)
>> [ 902.325813] [<c02cc12c>] (netlink_rcv_skb) from [<c02cc958>]
>> (genl_rcv+0x20/0x34)
>> [ 902.363540] [<c02cc958>] (genl_rcv) from [<c02cbaa8>]
>> (netlink_unicast+0x14c/0x1cc)
>> [ 902.399402] [<c02cbaa8>] (netlink_unicast) from [<c02cbe98>]
>> (netlink_sendmsg+0x2b8/0x39c)
>> [ 902.435798] [<c02cbe98>] (netlink_sendmsg) from [<c0297860>]
>> (sock_sendmsg+0x84/0xa8)
>> [ 902.477184] [<c0297860>] (sock_sendmsg) from [<c0298d28>]
>> (___sys_sendmsg.part.32+0x284/0x290)
>> [ 902.486197] [<c0298d28>] (___sys_sendmsg.part.32) from [<c0299d34>]
>> (__sys_sendmsg+0x4c/0x7c)
>> [ 902.555011] [<c0299d34>] (__sys_sendmsg) from [<c0009620>]
>> (ret_fast_syscall+0x0/0x44)
>> [ 902.591178] ---[ end trace 93a9f5360e80c5ca ]---
>>
>> I'm not sure if I should worry about this issue.
>
> Well, what is happening here is that the driver got a EAPOL message from
> the network stack to transmit and then got a key config request. That
> key config is held until transmit of EAPOL is completed. So it is
> suspicious.

By the way. This is a warning so not a kernel panic.

Regards,
Arend

> Regards,
> Arend
>
>> Best regards
>> Jörg Krause
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe
>> linux-wireless" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
> --
> To unsubscribe from this list: send the line "unsubscribe
> linux-wireless" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html