Hi,
     When I run 2 uml sessions using netkit , kernel version is 2.6.18.5, the uml sessions become very slow. On the command prompt I keep getting this message:
BUG: soft lockup detected on CPU#0!

The var/log/messages has a lot of stack trace dump of the following type:

                      dump_stack+0x1b/0x1f
 [<0808a61a>] softlockup_tick+0x7a/0x81
[<08079318>] run_local_timers+0x12/0x14
[<08079150>] update_process_times+0x3b/0x64
[<0805933d>] timer_handler+0x2c/0x4f
[<08069c1f>] user_signal+0x4b/0x5c
[<08069439>] userspace+0x214/0x240
[<0805aa31>] fork_handler+0x95/0x9d
[<b7fcd420>] 0xb7fcd420

Anybody can help me understand whats going on?

Thanks,
simha.