This fix has been accepted in 2.5

http://linux.bkbits.net:8080/linux-2.5/cset@1.1005?nav=index.html|ChangeSet@-1d

cut-n-paste from the checkin message:

We\'re calling mmdrop() under spin_lock_irq(&rq->lock).  But mmdrop
calls vfree(), which calls smp_call_function().

It is not legal to call smp_call_function() with irq\'s off.  Because
another CPU may be running smp_call_function() against _this_ CPU, which
deadlocks.

Our read of the code is that AS 2.1 is also susceptible to this problem.

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Action by: arunsharma
Issue Registered

ISSUE TRACKER 16281 by Intel as sev 3