Symptom:
Assertion failure at sess/sgsn/sgsn-app/dp/sn_dp_utran.c:557
  Function: sn_dp_utran_process_rx_setup_req_evt()
  Expression: pdu->u.rxSetupReq.peer_info.Inst.valid == 1
  Proclet: sessmgr (f=87000,i=348)
  Process: card=2 cpu=1 arch=X pid=8637 cpu=~3% argv0=sessmgr
  Crash time: 2014-Apr-16+03:37:10 UTC
  Recent errno: 11 Resource temporarily unavailable
  Stack (27496@0xffff7000):
    [ffffe430/X] __kernel_vsyscall() sp=0xffff74e8
    [0aa7f85f/X] sn_assert() sp=0xffff7528
    [071b7a15/X] sn_dp_utran_process_rx_setup_req_evt() sp=0xffff75c8
    [071cf7de/X] acc_dp_sm_receive_msg() sp=0xffff7668
    [06da2ad8/X] SmAppSendDpAccRxSetupReq() sp=0xffff7b18
    [06e674e9/X] sma_modify_send_rab_estab_req() sp=0xffff80c8
    [06e702c2/X] sma_ggsn_modify_pend_rab_rel_for_est_handle_rab_rel_resp() sp=0xffff8678
    [06cbf85a/X] sma_rsig_cfm() sp=0xffff8bf8
    [06e80484/X] access_sm_handle_rcvd_rapdu() sp=0xffff8c58
    [0723ff46/X] access_iu_handle_ranap_pdu_in_verified_or_ident_pending_2() sp=0xffff90e8
    [0724aef7/X] SNUiRptCnStInd() sp=0xffff9768
    [0c7e6d27/X] RaUiRptCnStInd() sp=0xffff97a8
    [0c7cc4c6/X] raLiCnRabAsgnRsp() sp=0xffff97c8
    [0c7bbad7/X] RaLiSptDatInd() sp=0xffff99a8
    [0c9427e7/X] SpUiSptDatInd() sp=0xffff99c8
    [0c931754/X] spDat1Tx() sp=0xffff9a38
    [0c93c139/X] spLiDataTx() sp=
    [0c90da54/X] SpLiSntUDatInd() sp=
    [0c906cf7/X] cmUnpkSntUDatInd() sp=
    [0c9412d4/X] spActvTsk() sp=
    [07f18830/X] skTskHdlr() sp=
    [07f0f365/X] SPstTsk() sp=
    [07f22348/X] sn_process_pst_req() sp=
    [07f22a93/X] sn_handle_ccpu_bulk_req_msg() sp=

Conditions:
This crash is seen in system-test setup, when there was an overnight call model run.