Description of problem: Repeatedly turning on and off of a group of
ethernet interfaces (ifup and ifdown) in a system causes a kernel
panic.  The types of ethernet NICs don't seem to matter.  I've done
this with Broadcom 10/100/1000 cards, e1000 cards and quad cards (DEC
4 port 10/100 cards).  It doesn't seem to happen with just two
interfaces, but with 4 and above it always happens.


Version-Release number of selected component (if applicable):
RHEL 3.0 Update 1 (2.4.21-9.EL)

How reproducible:  Repeatedly ifup and ifdown interfaces (more than 2;
less than 7); the kernel panic will happen within the hour


Steps to Reproduce:
1
.use these scripts:

#!/usr/bin/ksh
# startMcaGen by Rick Burchett
mcaGen2 eth1&
sleep 1
mcaGen2 eth2&
sleep 1
mcaGen2 eth3&
sleep 1
mcaGen2 eth4&


#!/usr/bin/ksh
#mcaGen2 by Rick Burchett
#set -x
# get starting seconds
let sSeconds=$(date +%s)

getElapsedTime() {
   #get current seconds
   let cSeconds=$(date +%s)
   ((eSeconds=cSeconds - sSeconds))
   #compute elapsed time
   ((hours=(eSeconds / 60)/60))
   ((eSeconds-=hours * 60 * 60))
   ((minutes=eSeconds / 60))
   ((seconds=eSeconds - minutes * 60))

   print "Elapsed time: $hours:$minutes:$seconds"
}


while true
do
        echo "Shutting down $1"
                ifdown $1
        echo "$1 shutdown; Sleeping for 15 seconds"
        getElapsedTime
        #sleep 15
        echo "Starting up $1"
        ifup $1
        echo -n "Pinging $1"
        echo
        # INSERT AN ADDRESS TO PING HERE WITH THE PING COMMAND
                  #ping -c 100 -i 0 <ipaddr>
        echo "Sleeping for 15 seconds"
        getElapsedTime
        sleep 15
        getElapsedTime
done


2. Edit startMcaGen to reflect your environment
   edit mcaGen2 to work in your environment
3. Run startMcaGen
  
Actual results:Kernel panic after several minutes (less than an hour
in all observed tests)


Expected results: No kernel panic


Additional info:
Sleeping for 15 seconds
Elapsed time: 0:18:47
Elapsed time: 0:18:47
Elapsed time: 0:18:45
Shutting down eth9
Shutting down eth7
Elapsed time: 0:18:44
Shutting down eth10
Elapsed time: 0:18:46
Shutting down eth8
eth7 shutdown; Sleeping for 15 seconds
eth8 shutdown; Sleeping for 15 seconds
Elapsed time: 0:18:47
Starting up eth7
eth10 shutdown; Sleeping for 15 seconds
Elapsed time: 0:18:46
ip_tables: (C) 2000-2002 Netfilter core team
Starting up eth8
eth9 shutdown; Sleeping for 15 seconds
Elapsed time: 0:18:44
Starting up eth10
Elapsed time: 0:18:45
Starting up eth9
Unable to handle kernel paging request at virtual address a0000000004710d0
modprobe[13965]: Oops 8813272891392

Pid: 13965, comm:             modprobe
EIP is at .plt [iptable_filter] 0x130 (2.4.21-9.EL)
psr : 0000101008026038 ifs : 8000000000000001 ip  :
[<a0000000017111f0>]    Tainted: GF
unat: 0000000000000000 pfs : 0000000000000286 rsc : 0000000000000003
rnat: 0000000000000000 bsps: e000000004cabd00 pr  : 80000000f5a59619
ldrs: 0000000000000000 ccv : 0000000080000000 fpsr: 0009804c0270033f
b0  : a0000000017104c0 b6  : e00000000471ef80 b7  : a000000001710440
f6  : 1003e6db6db6db6db6db7 f7  : 1003e6000000000027e00
f8  : 1003e000000000002ec5f f9  : 1003efffffffffffffe03
r1  : a000000001711050 r2  : a000000001711050 r3  : 0000000000000000
r8  : a000000000008008 r9  : 0000000000000001 r10 : 0000000000000060
r11 : 0000000000000003 r12 : e00000011bd87e50 r13 : e00000011bd80000
r14 : 0000000080000000 r15 : a0000000004710d0 r16 : a000000001711240
r17 : 0000000000000004 r18 : e000000004b6a844 r19 : 000000007fffffff
r20 : 0000000000000004 r21 : e000000004b6a6c0 r22 : e000000004acad20
r23 : 0000000080000000 r24 : 0000000000000000 r25 : 0000000000000000
r26 : 0000000000000000 r27 : 0000000000000000 r28 : 0000000000000000
r29 : 0000000080000000 r30 : 0000000000000000 r31 : a000000001710048

Call Trace: [<e000000004415620>] sp=0xe00000011bd87a60
bsp=0xe00000011bd81318 show_stack [kernel] 0x80
[<e000000004430550>] sp=0xe00000011bd87c20 bsp=0xe00000011bd812e8 die
[kernel] 0x1b0
[<e0000000044527f0>] sp=0xe00000011bd87c20 bsp=0xe00000011bd81290
ia64_do_page_fault [kernel] 0x310
[<e00000000440e6e0>] sp=0xe00000011bd87cb0 bsp=0xe00000011bd81290
ia64_leave_kernel [kernel] 0x0
[<a0000000017111f0>] sp=0xe00000011bd87e50 bsp=0xe00000011bd81288 .plt
[iptable_filter] 0x130
[<a0000000017104c0>] sp=0xe00000011bd87e50 bsp=0xe00000011bd81260 fini
[iptable_filter] 0x80
[<e00000000448c6f0>] sp=0xe00000011bd87e50 bsp=0xe00000011bd81230
free_module [kernel] 0x390
[<e00000000448a340>] sp=0xe00000011bd87e50 bsp=0xe00000011bd81180
sys_delete_module [kernel] 0x3c0
[<e00000000440e6c0>] sp=0xe00000011bd87e60 bsp=0xe00000011bd81180
ia64_ret_from_syscall [kernel] 0x0
Kernel panic: Fatal exception