crash since commit "net/flow_dissector: switch to siphash"

[Koen Vandeputte <koen.vandeputte@ncentric.com>]

Hi Eric,

I'm currently testing kernel 4.14.153 bump for OpenWrt and noticed splat 
below on my testing boards.
They all reboot continuously nearly immediately when linked.

It feels like it's tied to a commit of yours [1]

Any idea?

If you need more info, please let me know.

Thanks,

Koen


[1]: 
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v4.14.154&id=a9de6f42e945cdb24b59c7ab7ebad1eba6cb5875


[   48.269789] wlan0: Trigger new scan to find an IBSS to join
[   48.680754] wlan0: Trigger new scan to find an IBSS to join
[   49.041907] wlan0: Trigger new scan to find an IBSS to join
[   49.079668] wlan0: Trigger new scan to find an IBSS to join
[   49.149738] wlan0: Selected IBSS BSSID 16:5b:94:39:cb:5f based on 
configured SSID
[   49.199633] Unhandled kernel unaligned access[#1]:
[   49.204505] CPU: 0 PID: 1634 Comm: wpa_supplicant Tainted: G        
W       4.14.153 #0
[   49.212619] task: 87d14580 task.stack: 860c6000
[   49.217209] $ 0   : 00000000 77ea0b33 00000000 ceb5840c
[   49.222515] $ 4   : 860c7a78 00000014 67aae3bf 00000000
[   49.227821] $ 8   : 00000000 8040c9b0 87d1e460 0000d000
[   49.233128] $12   : 74650000 00000000 00000001 00000002
[   49.238435] $16   : 0000fffe 804f0000 67aae3bf 8766e5a4
[   49.243741] $20   : 00000000 804f0000 804f3978 87d1e054
[   49.249048] $24   : 00000002 00000003
[   49.254353] $28   : 860c6000 860c7a30 00000000 8032cff8
[   49.259661] Hi    : 00000050
[   49.262573] Lo    : 00000002
[   49.265500] epc   : 804061a4 __siphash_aligned+0x24/0x730
[   49.270985] ra    : 8032cff8 skb_get_hash_perturb+0x160/0x1a8
[   49.276803] Status: 1100dc03 KERNEL EXL IE
[   49.281045] Cause : 00800010 (ExcCode 04)
[   49.285110] BadVA : 67aae3c7
[   49.288024] PrId  : 00019750 (MIPS 74Kc)
[   49.291990] Modules linked in: mbt ath9k ath9k_common qcserial pppoe 
ppp_async option cdc_mbim ath9k_hw ath10k_pci ath10k_core ath usb_wwan 
sierra_net sierra rndis_host qmi_wwan pppox ppp_generic mac80211 
iptable_nat iptable_mangle iptable_filter ipt_REJECT ipt_MASQUERADE 
ip_tables huawei_cdc_ncm ftdi_sio cfg80211 cdc_subset cdc_ncm cdc_ether 
xt_time xt_tcpudp xt_state xt_nat xt_multiport xt_mark xt_mac xt_lim2
[   49.363914]  cls_tcindex cls_route cls_matchall cls_fw cls_flow 
cls_basic act_skbedit act_mirred i2c_dev ledtrig_usbport cryptodev msdos 
bonding ip_gre gre dummy udp_tunnel ip_tunnel tun vfat fat nls_utf8 
nls_iso8859_1 nls_cp437 authenc ehci_platform sd_mod scsi_mod ehci_hcd 
gpio_button_hotplug ext4 mbcache jbd2 usbcore nls_base usb_common ptp 
pps_core mii aead crypto_null cryptomgr crc32c_generic crypto_hash
[   49.400738] Process wpa_supplicant (pid: 1634, threadinfo=860c6000, 
task=87d14580, tls=77f6defc)
[   49.409638] Stack : 67aae3bf 0000fffe 804f0000 67aae3bf 8766e5a4 
00000000 804f0000 804f3978
[   49.418121]         00000056 80580000 879b84c8 879cb088 00000000 
00000000 00000085 00000004
[   49.426604]         00220000 00000000 888e0000 00000000 00000000 
00000000 00000000 00000000
[   49.435087]         00000000 00000000 00000000 00000000 00000000 
00000000 00000000 00000000
[   49.443570]         860c7b68 ceb5840c 86cb0bc0 860c2300 8766e508 
86d2b604 879cb088 8793a750
[   49.452053]         ...
[   49.454537] Call Trace:
[   49.457014] [<804061a4>] __siphash_aligned+0x24/0x730
[   49.462146] [<8032cff8>] skb_get_hash_perturb+0x160/0x1a8
[   49.467737] [<86d2b604>] ieee80211_reserve_tid+0x26c/0xeb8 [mac80211]
[   49.474300] Code: afb2000c  afb10008  afb00004 <8cd40008> 8cc90000  
3c136c79  3c02646f  3c07736f  24427261
[   49.484200]
[   49.485774] ---[ end trace ec8947d373843bf7 ]---
[   49.492228] Kernel panic - not syncing: Fatal exception in interrupt
[   49.499642] Rebooting in 3 seconds..