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User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.12) Gecko/20050915 Firefox/1.0.7

Description of problem:
If you try and install using the FC4 x86_64 ISO boot disc, it crashes as it is booting just after:

md: ...autorun DONE.

with the message:

VFS: Cannot open root device "<NULL>" or unknown-block(3,2)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(3,2)

Call Trace: <ffffffff8013a4a5>{panic+133} <ffffffff801cba74>{sys_mount+196}
<ffffffff801f6ef9>{__bdevname+41} <ffffffff80582c00>{mount_block_root+496}
<ffffffff80582d85>{prepare_namespace+213} <ffffffff801c186>{init+326}
<ffffffff8010fc33>{chip_rip+8} <ffffffff8010c040>{init+0}
<ffffffff8010fc2b>{chip_rip+0}
<3>BUG: soft lockup detected on CPU#0!


NOTES:

I even tried removing one CPU to see if that helped.  FC3 boot iso for x86_64 does not exhibit this behavior and I will have to reinstall my system again using FC3.

Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1. insert boot iso turn on machine
2. watch it boot
3. watch it crash
  

Actual Results:  same as above

Expected Results:  boots and anaconda starts.

Additional info: