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User-Agent: Mozilla/5.0 (X11; U; Linux i686; ja-JP; rv:1.4) Gecko/20030930
Debian/1.4-5

Description of problem:
On SMP machine boot-up, the operating system may stall
while fork-ing processes from /sbin/init.

The stall occurs randomly.
Usually after invoking /sbin/init and before showing login prompt.

This can be fixed by the patch recently posted to linux-ia64.org.

Version-Release number of selected component (if applicable):
kernel-2.4.21-3.EL

How reproducible:
Sometimes

Steps to Reproduce:
1. Boot-up on SMP machine
2. (repeat step 1)
3.
    

Actual Results:  Boot-up process will stall somewhere after invoking rc script.

For example, it may stall after printing the following message:
  Remounting root filesystem in read-write mode:  [  OK  ]
  Activating swap partitions:  [  OK  ]
  Finding module dependencies:  [  OK  ]


Expected Results:  Eventually, login prompt should appear on console.

Additional info:

The problem is caused by wrong setup of initial value of
kr[CURRENT_STACK] which is used in ia64_switch_to()
to determine if the kernel address is already mapped.
ia64_switch_to() assumes the value of this register should be
based on the kernel granule size (16MB for current configuration).
But its initial value is wrongly calculated based on 64MB.
Thus, during the first task switch, the kernel could take
unmapped address as already mapped, refer to it and fall into
infinite TLB miss loop.

The patch to fix this problem was posted to linux-ia64.org
with subject "wrong initial ia64_kr(current_stack) value" at Oct. 9
by Chenn, Kenneth W.
http://marc.theaimsgroup.com/?l=linux-ia64&m=106571413927132&w=2