LTC Owner is: csiddali.com
LTC Originator is: shaowu.com


Problem description:
We boot system leto.upt.austin.ibm.com from CD (boot.iso), then do network nfs
install. Everything works normal until puting the nfs server ip and install 
directory. It hangs for a while (1 or 2 hours), and finally goes to xmon. 
another system medusalp1 does not have this kind of problem.

Hardware Environment
    Machine type (p650, x235, SF2, etc.): 9113-550
    Cpu type (Power4, Power5, IA-64, etc.): power5

Is this reproducible?  Yes.
    If so, how long does it (did it) take to reproduce it? 30 minutes.
    Describe the steps:
    1. reboot the system from fsp-leto,
    2. go to SMS, then select IDE CD install, or network install for eth0
    3. select NFS network isntall. 

Is the system (not just the application) hung? Yes.
    If so, describe how you determined this:  it goes to xmon

Is the system sitting in a debugger right now? Yes.


Additional information:
1:mon> e
cpu 0x1: Vector: 300 (Data Access) at [c00000000fff3ae0]
    pc: c00000000021e93c: .hvsi_interrupt+0x198/0x4dc
    lr: c00000000021e804: .hvsi_interrupt+0x60/0x4dc
    sp: c00000000fff3d60
   msr: 8000000000001032
   dar: 128
 dsisr: 40000000
  current = 0xc000000073f96000
  paca    = 0xc00000000045e300
    pid   = 0, comm = swapper
1:mon> r
R00 = 0000000000000040   R16 = 0000000000000000
R01 = c00000000fff3d60   R17 = 0000000000000000
R02 = c000000000576058   R18 = 0000000000000000
R03 = 000000000000000a   R19 = 0000000000000000
R04 = 000000000000000a   R20 = 0000000000000000
R05 = 00000000000000fe   R21 = 0000000000000000
R06 = 0001000000000000   R22 = 8000000000001032
R07 = 0000000000000000   R23 = 0000000000000000
R08 = c00000000fff3cc0   R24 = c0000000005ec560
R09 = 0000000000000000   R25 = c0000000005ec4a8
R10 = c0000000005ec568   R26 = c000000073fbfb50
R11 = 80000000001372e8   R27 = 0000000000000000
R12 = 0000000000004000   R28 = c0000000005ec398
R13 = c00000000045e300   R29 = 0000000000000000
R14 = 0000000000000000   R30 = c0000000004e2390
R15 = 0000000007a852ec   R31 = c0000000005ec560
pc  = c00000000021e93c .hvsi_interrupt+0x198/0x4dc
lr  = c00000000021e804 .hvsi_interrupt+0x60/0x4dc
msr = 8000000000001032   cr  = 28000042
ctr = 80000000001372e8   xer = 000000000000000a   trap =  300
dar = 0000000000000128   dsisr = 40000000
1:mon> di c00000000021e93c
c00000000021e93c  e81b0128      ld      r0,296(r27)
c00000000021e940  780b8fe3      rldicl. r11,r0,49,63
c00000000021e944  40a20180      bne     c00000000021eac4        
# .hvsi_interrupt+0x320/0x4dc
c00000000021e948  881f0001      lbz     r0,1(r31)
c00000000021e94c  3b400000      li      r26,0
c00000000021e950  4800001c      b       c00000000021e96c        
# .hvsi_interrupt+0x1c8/0x4dc
c00000000021e954  881c02f6      lbz     r0,758(r28)
c00000000021e958  2f800000      cmpwi   cr7,r0,0
c00000000021e95c  419e0168      beq     cr7,c00000000021eac4    
# .hvsi_interrupt+0x320/0x4dc
c00000000021e960  881f0001      lbz     r0,1(r31)
c00000000021e964  7f9ae378      mr      r26,r28
c00000000021e968  3b600000      li      r27,0
c00000000021e96c  7fff0214      add     r31,r31,r0
c00000000021e970  4800018c      b       c00000000021eafc        
# .hvsi_interrupt+0x358/0x4dc
c00000000021e974  e89c012a      lwa     r4,296(r28)
c00000000021e978  e87e8098      ld      r3,-32616(r30)
1:mon> t
[c00000000fff3e30] c000000000092454 .handle_IRQ_event+0x7c/0xf8
[c00000000fff3ee0] c00000000009264c .__do_IRQ+0x17c/0x23c
[c00000000fff3f90] c000000000025628 .call___do_IRQ+0x14/0x24
[c000000073fbfa50] c00000000000bd7c .do_IRQ+0xcc/0x148
[c000000073fbfae0] c0000000000041ec hardware_interrupt_entry+0xc/0x10
--- Exception: 501 (Hardware Interrupt) at 
c000000000042330 .plpar_hcall_norets+0x10/0x1c
[link register   ] c0000000000436f8 .pseries_dedicated_idle_sleep+0x1a0/0x1e8
[c000000073fbfdd0] 0000000073fbfe80 (unreliable)
[c000000073fbfe80] c000000000011060 .cpu_idle+0x10c/0x1e0
[c000000073fbff00] c000000000028c34 .start_secondary+0x144/0x168
[c000000073fbff90] c0000000000083bc .start_secondary_prolog+0xc/0x10
1:mon>


With latest GA7 sp1 firmware, and COD applied. The system goes to xmon as 
before.


I used kernel-2.6.16-1.2202_FC6.src.rpm to look at the dis-assembly. 
From the dis-assembly ...

1:mon> di c00000000021e93c
c00000000021e93c  e81b0128      ld      r0,296(r27)
c00000000021e940  780b8fe3      rldicl. r11,r0,49,63
c00000000021e944  40a20180      bne     c00000000021eac4        

Looks like were executing the following line ...

static void hvsi_recv_control(struct hvsi_struct *hp....... )
{
...
 switch (header->verb) {
      case VSV_MODEM_CTL_UPDATE:
          if ((header->word & HVSI_TSCD) == 0) {
          /* CD went away; no more connection */
          pr_debug("hvsi%i: CD dropped\n", hp->index);
          hp->mctrl &= TIOCM_CD;
          if (!(hp->tty->flags & CLOCAL))  <<<<<<--------- here 
             *to_hangup = hp->tty;