On Wed, Jun 17, 2015 at 10:31:40AM +0530, Vivek Bhagat wrote: > Hi All, > > I have connected my pc and TV board as below - > > PC (network i/f) <----> ethernet to usb dongle <---> usb port of TV board > > When I power off my board, i get a kernel crash. > Please have a look at log attached here.I debug and found that > unregister_netdev() in usbnet_disconnect() clears net_device object > and still skb is under processing which tries to access net_device > object and leads to crash.Dongle is using ax88179_178.ko module. > > Backtrace: > [1-11856.1782] [<c045ea38>] (fib_compute_spec_dst+0x0/0x17c) from > [<c04308c0>] (ipv4_pktinfo_prepare+0x38/0x70) > [1-11856.1880] r6:00000000 r5:c5d55800 r4:c5d55800 > [1-11856.1926] [<c0430888>] (ipv4_pktinfo_prepare+0x0/0x70) from > [<c04512d4>] (udp_queue_rcv_skb+0x1c8/0x384) > [1-11856.2023] r5:c5d55800 r4:cbdf4380 > [1-11856.2059] [<c045110c>] (udp_queue_rcv_skb+0x0/0x384) from > [<c0451590>] (flush_stack+0x100/0x118) > [1-11856.2148] r7:cd398480 r6:00000000 r5:cbdf4380 r4:c5d55800 > [1-11856.2205] [<c0451490>] (flush_stack+0x0/0x118) from [<c04518b0>] > (__udp4_lib_mcast_deliver.isra.44+0x308/0x370) > [1-11856.2308] [<c04515a8>] > (__udp4_lib_mcast_deliver.isra.44+0x0/0x370) from [<c0451dd0>] > (__udp4_lib_rcv+0x4b8/0x588) > [1-11856.2413] [<c0451918>] (__udp4_lib_rcv+0x0/0x588) from > [<c0451ec0>] (udp_rcv+0x20/0x28) > [1-11856.2495] [<c0451ea0>] (udp_rcv+0x0/0x28) from [<c042836c>] > (ip_local_deliver_finish+0x118/0x27c) > [1-11856.2585] [<c0428254>] (ip_local_deliver_finish+0x0/0x27c) from > [<c0428988>] (ip_local_deliver+0x8c/0x98) > [1-11856.2683] r7:d4b01a40 r6:cd398480 r5:00000000 r4:cd398480 > [1-11856.2740] [<c04288fc>] (ip_local_deliver+0x0/0x98) from > [<c0428798>] (ip_rcv_finish+0x2c8/0x344) > [1-11856.2829] r4:00295a38 > [1-11856.2855] [<c04284d0>] (ip_rcv_finish+0x0/0x344) from > [<c0428cb8>] (ip_rcv+0x324/0x3f0) > [1-11856.2936] r7:d4b01a40 r6:cd398480 r5:d2e8b720 r4:c0737500 > [1-11856.2993] [<c0428994>] (ip_rcv+0x0/0x3f0) from [<c03f69d4>] > (__netif_receive_skb_core+0x4d0/0x568) > [1-11856.3084] r7:00000000 r6:00000000 r5:c0708b34 r4:c070a728 > [1-11856.3141] [<c03f6504>] (__netif_receive_skb_core+0x0/0x568) from > [<c03f7038>] (__netif_receive_skb+0x20/0x70) > [1-11856.3242] [<c03f7018>] (__netif_receive_skb+0x0/0x70) from > [<c03f8584>] (process_backlog+0xec/0x1e8) > [1-11856.3335] r5:00000000 r4:d7c828c4 > [1-11856.3371] [<c03f8498>] (process_backlog+0x0/0x1e8) from > [<c03f82e4>] (net_rx_action+0x104/0x2b8) > [1-11856.3460] [<c03f81e0>] (net_rx_action+0x0/0x2b8) from > [<c0044460>] (__do_softirq+0x180/0x304) > [1-11856.3548] [<c00442e0>] (__do_softirq+0x0/0x304) from [<c0044708>] > (do_softirq+0x74/0xc4) > [1-11856.3630] [<c0044694>] (do_softirq+0x0/0xc4) from [<c03f56f0>] > (netif_rx_ni+0x50/0x78) > [1-11856.3711] r7:d1708780 r6:cd399380 r5:00000000 r4:c850a020 > [1-11856.3768] [<c03f56a0>] (netif_rx_ni+0x0/0x78) from [<c03f57ec>] > (dev_loopback_xmit+0xd4/0xe0) > [1-11856.3855] r5:00000000 r4:cd398480 > [1-11856.3891] [<c03f5718>] (dev_loopback_xmit+0x0/0xe0) from > [<c042da08>] (ip_mc_output+0x114/0x234) > [1-11856.3980] r5:00000000 r4:cd398480 > [1-11856.4016] [<c042d8f4>] (ip_mc_output+0x0/0x234) from [<c042d3cc>] > (ip_local_out+0x38/0x3c) > [1-11856.4100] r9:000000c6 r8:d2e8b734 r7:cbdf7800 r6:c0737500 r5:c0737500 > r4:cd399380 > [1-11856.4179] [<c042d394>] (ip_local_out+0x0/0x3c) from [<c042e5bc>] > (ip_send_skb+0x20/0x88) > [1-11856.4261] r5:c0737500 r4:cd399380 > [1-11856.4297] [<c042e59c>] (ip_send_skb+0x0/0x88) from [<c044e400>] > (udp_send_skb+0x250/0x314) > [1-11856.4382] r5:00000000 r4:cd399380 > [1-11856.4417] [<c044e1b0>] (udp_send_skb+0x0/0x314) from [<c04505b4>] > (udp_sendmsg+0x6a8/0x6d0) > [1-11856.4503] [<c044ff0c>] (udp_sendmsg+0x0/0x6d0) from [<c04587a8>] > (inet_sendmsg+0x94/0xc4) > [1-11856.4586] [<c0458714>] (inet_sendmsg+0x0/0xc4) from [<c03e2624>] > (sock_sendmsg+0xa0/0xbc) > [1-11856.4670] r7:c8406e40 r6:c850bf5c r5:000000be r4:c4cda300 > [1-11856.4726] [<c03e2584>] (sock_sendmsg+0x0/0xbc) from [<c03e3c2c>] > (___sys_sendmsg.part.16+0x1a0/0x244) > [1-11856.4820] r7:c4cda300 r6:00000000 r5:c850be7c r4:00000000 > [1-11856.4877] [<c03e3a8c>] (___sys_sendmsg.part.16+0x0/0x244) from > [<c03e4db4>] (__sys_sendmsg+0x5c/0x80) > [1-11856.4971] [<c03e4d58>] (__sys_sendmsg+0x0/0x80) from [<c03e4df0>] > (SyS_sendmsg+0x18/0x1c) > [1-11856.5055] r6:bdfda694 r5:bdfda60c r4:002841c0 > [1-11856.5101] [<c03e4dd8>] (SyS_sendmsg+0x0/0x1c) from [<c00114c0>] > (ret_fast_syscall+0x0/0x48) 3.10 is really old, please try something more "modern" like 4.0 at the very least to see if the issue is still there. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html