K 10
svn:author
V 4
neel
K 8
svn:date
V 27
2010-02-10T05:43:31.665756Z
K 7
svn:log
V 490
Enable interrupts before doing AST processing to avoid a deadlock.

Specifically on an SMP kernel it was observed that if both the
processors are doing an exit1() via ast()->postsig()->sigexit()
then we will deadlock.

This happens because exit1() calls vmspace_exit() that in turn
calls pmap_invalidate_all(). This function tries to do a
smp_rendezvous() which blocks because the other processor is not
responding to IPIs - because it too is doing AST processing with
interrupts disabled.

END