Kernel error
Hi Guys,
I am getting the following kernel error while doing some experiments.
Any idea where things are going wrong. To me it looks like there is an
error while copying data from user space to kernel space. The
application which i am running is iperf. However i also have netem
module for emulating some wide area network characteristics like
delay. I am using delay of 100ms.
##Error Message#
Unable to handle kernel NULL pointer dereference at virtual address 0004
printing eip:
c02fee3c
*pde = 7ded4067
Oops: 0002 [#5]
Modules linked in: setparam(U) sch_netem(U) nfs(U) lockd(U) autofs4(U)
sunrpc(U)CPU:0
EIP:0060:[c02fee3c]Not tainted VLI
EFLAGS: 00010286 (2.6.12-1.1390_FC4-emulab-1)
EIP is at tcp_transmit_skb+0x3ef/0x8de
eax: ebx: f71a1a40 ecx: ed64f960 edx: ed64ff60
esi: edi: f2f98500 ebp: ed71b780 esp: f47bddd4
ds: 007b es: 007b ss: 0068
Process iperf (pid: 2443, threadinfo=f47bc000 task=f71a1a40)
Stack: f2f9854c c02d1019 ed71b7b8 f2f98500 ed15cc80 0282 ed71b780 0100
c02ce99f f71a1a40 f2f98500 f71a1a40 f2f98500 f2f9854c c02f53ad
ed335db8 f2f98500 f2f98500 f47bdeb8 002ce99f
Call Trace:
[c02d1019] skb_copy_datagram_iovec+0x180/0x1f8
[c02ce99f] alloc_skb+0x31/0xc1
[c02f53ad] tcp_recvmsg+0x2b1/0x74e
[c02fd83f] tcp_rcv_established+0x5d2/0x77a
[c02ce2e0] sock_common_recvmsg+0x41/0x57
[c02cb052] sock_aio_read+0xf9/0x12b
[c014fccb] do_sync_read+0x9e/0xec
[c01291ae] autoremove_wake_function+0x0/0x37
[c014fe23] vfs_read+0x10a/0x10e
[c0150064] sys_read+0x41/0x6a
[c0102d29] syscall_call+0x7/0xb
Code: a1 04 07 39 c0 e8 c0 e5 e3 ff 89 c2 85 c0 74 2d 83 87 08 04 00 00 01 8b 8
#
Thanks in advance
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