Description of problem:
occured at system start

Additional info:
kernel BUG at net/sunrpc/svc_xprt.c:921!
invalid opcode: 0000 [#1] SMP 
Modules linked in: nfsv4 auth_rpcgss nfs dns_resolver fscache lockd sunrpc bnep bluetooth rfkill mpt2sas raid_class scsi_transport_sas snd_hda_codec_realtek snd_hda_intel snd_hda_codec coretemp snd_hwdep kvm_intel iTCO_wdt snd_seq snd_seq_device snd_pcm kvm iTCO_vendor_support r8169 snd_page_alloc snd_timer snd lpc_ich i2c_i801 ppdev mii mfd_core soundcore parport_pc parport microcode uinput i915 video i2c_algo_bit drm_kms_helper drm i2c_core
CPU 0 
Pid: 1238, comm: nfsv4.0-svc Not tainted 3.7.6-201.fc18.x86_64 #1 O.E.M O.E.M/G41MXE-V
RIP: 0010:[<ffffffffa035547a>]  [<ffffffffa035547a>] svc_delete_xprt+0x12a/0x130 [sunrpc]
RSP: 0018:ffff88003693be28  EFLAGS: 00010286
RAX: 00000000ffffffff RBX: ffff8800c11b6000 RCX: dead000000200200
RDX: ffff8800bf02b698 RSI: 7fffffffffffffff RDI: ffff8800c2592000
RBP: ffff88003693be48 R08: ffff8800c2592028 R09: 00000000000a60f8
R10: 00000000000036bb R11: 0000000000000000 R12: ffff8800c2592000
R13: ffff880036e05000 R14: 0000000000000000 R15: ffff880036e05000
FS:  0000000000000000(0000) GS:ffff8800c7a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000003adf0bb750 CR3: 00000000c14b2000 CR4: 00000000000407f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process nfsv4.0-svc (pid: 1238, threadinfo ffff88003693a000, task ffff8800c0d70000)
Stack:
 ffff8800c11b6000 ffff8800c2592000 ffff880036e05000 0000000000000000
 ffff88003693be98 ffffffffa0356a41 ffff880036e05000 ffff8800c11b6000
 ffff880036e05000 ffff8800c11b6000 ffff8800c11b6000 ffffffffa040e830
Call Trace:
 [<ffffffffa0356a41>] svc_recv+0x101/0x580 [sunrpc]
 [<ffffffffa040e830>] ? nfs_callback_authenticate+0x50/0x50 [nfsv4]
 [<ffffffffa040e86b>] nfs4_callback_svc+0x3b/0x60 [nfsv4]
 [<ffffffff81081e00>] kthread+0xc0/0xd0
 [<ffffffff81010000>] ? ftrace_raw_event_xen_mmu_flush_tlb_others+0x50/0xe0
 [<ffffffff81081d40>] ? kthread_create_on_node+0x120/0x120
 [<ffffffff8163f22c>] ret_from_fork+0x7c/0xb0
 [<ffffffff81081d40>] ? kthread_create_on_node+0x120/0x120
Code: f7 e8 eb 65 fa e0 4d 89 74 24 18 4d 89 74 24 20 e9 49 ff ff ff 48 89 fe 31 c0 48 c7 c7 03 c3 35 a0 e8 14 77 2d e1 e9 0a ff ff ff <0f> 0b 0f 0b 66 90 66 66 66 66 90 f0 80 4f 38 04 f0 0f ba 6f 38 
RIP  [<ffffffffa035547a>] svc_delete_xprt+0x12a/0x130 [sunrpc]
 RSP <ffff88003693be28>