In Linux initrd image, ethernet fails to work

viveksundarthir · ‎11-18-2014

I am working on SABRE SD Development board, which uses i.Mx6 Quad core processor. I have developed a initrd image for this board. The kernel boots up and the initrd images is mounted successfully. Even the fec ethernet drivers are loaded properly.

But during the init process the dhcp fails to designate an ip for the ethernet device. On analysis using the strace utility on the 'dhcp' command the following log was obtained: In the log a select system call Timeouts causing the error. A selective portion of the log is given bellow. The timeout is highlighted.

write(1, "Sending discover...\n", 20Sending discover...

) = 20

socket(PF_PACKET, SOCK_DGRAM, 8) = 6

bind(6, {sa_family=AF_PACKET, proto=0x800, if2, pkttype=PACKET_HOST, addr(6)={0, ffffffffffff}, 20) = 0

sendto(6, "E\0\0014\0\0\0\0@\21y\272\0\0\0\0\377\377\377\377\0D\0C\1 ,h\1\1\6\0"..., 308, 0, {sa_family=AF_PACKET, proto=0x800, if2, pkttype=PACKET_HOST, add8

close(6) = 0

fcntl64(5, F_SETFD, FD_CLOEXEC) = 0

clock_gettime(CLOCK_MONOTONIC, {53, 990583005}) = 0

select(6, [3 5], NULL, NULL, {3, 0}) = 0 (Timeout)

And after some time with the dhcp with strace running a kernel crash is observed the crash dump is as follows:

udhcpc (v1.21.1) started

Sending discover...

------------[ cut here ]------------

WARNING: at net/sched/sch_generic.c:255 dev_watchdog+0x288/0x294()

NETDEV WATCHDOG: eth0 (fec): transmit queue 0 timed out

Modules linked in:

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.17+gec1af9f #17

[<80013b44>] (unwind_backtrace+0x0/0xf4) from [<80011564>] (show_stack+0x10/0x14)

[<80011564>] (show_stack+0x10/0x14) from [<80025e60>] (warn_slowpath_common+0x54/0x6c)

[<80025e60>] (warn_slowpath_common+0x54/0x6c) from [<80025ea8>] (warn_slowpath_fmt+0x30/0x40)

[<80025ea8>] (warn_slowpath_fmt+0x30/0x40) from [<804c5c5c>] (dev_watchdog+0x288/0x294)

[<804c5c5c>] (dev_watchdog+0x288/0x294) from [<80032f0c>] (call_timer_fn.isra.30+0x24/0x88)

[<80032f0c>] (call_timer_fn.isra.30+0x24/0x88) from [<80033104>] (run_timer_softirq+0x194/0x210)

[<80033104>] (run_timer_softirq+0x194/0x210) from [<8002d1d4>] (__do_softirq+0x124/0x204)

[<8002d1d4>] (__do_softirq+0x124/0x204) from [<8002d364>] (do_softirq+0x54/0x5c)

[<8002d364>] (do_softirq+0x54/0x5c) from [<8002d5ec>] (irq_exit+0x9c/0xd0)

[<8002d5ec>] (irq_exit+0x9c/0xd0) from [<8000e84c>] (handle_IRQ+0x44/0x90)

[<8000e84c>] (handle_IRQ+0x44/0x90) from [<80008570>] (gic_handle_irq+0x2c/0x5c)

[<80008570>] (gic_handle_irq+0x2c/0x5c) from [<8000dbc0>] (__irq_svc+0x40/0x50)

Exception stack(0x80bddf20 to 0x80bddf68)

BUG: scheduling while atomic: swapper/0/0/0x40000100

Modules linked in:

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.17+gec1af9f #17

[<80013b44>] (unwind_backtrace+0x0/0xf4) from [<80011564>] (show_stack+0x10/0x14)

[<80011564>] (show_stack+0x10/0x14) from [<805d4c9c>] (__schedule_bug+0x50/0x64)

[<805d4c9c>] (__schedule_bug+0x50/0x64) from [<805d9e2c>] (__schedule+0x534/0x5a8)

[<805d9e2c>] (__schedule+0x534/0x5a8) from [<8004d5e8>] (__cond_resched+0x24/0x34)

[<8004d5e8>] (__cond_resched+0x24/0x34) from [<805da20c>] (_cond_resched+0x3c/0x44)

[<805da20c>] (_cond_resched+0x3c/0x44) from [<80011418>] (dump_mem+0xd0/0x140)

[<80011418>] (dump_mem+0xd0/0x140) from [<80013bb4>] (unwind_backtrace+0x70/0xf4)

[<80013bb4>] (unwind_backtrace+0x70/0xf4) from [<80011564>] (show_stack+0x10/0x14)