K 10
svn:author
V 6
marcel
K 8
svn:date
V 27
2003-05-20T02:52:41.000000Z
K 7
svn:log
V 738
Prevent corruption of the VHPT collision chain by protecting it with
a mutex. The only volatile chain operations are insertion and deletion
but since updating an existing PTE also updates the VHPT entry itself,
and we have the VHPT mutex in both other cases, we also lock when we
update an existing PTE even though no chain operation is involved.
Note that we perform the insertion and deletion careful enough that
we don't need to lock traversals. If we need to lock traversals, we
also need to lock from the exception handler, which we can't without
creating a trapframe.

We're now able to withstand a -j8 buildworld. More work is needed to
withstand Murphy fields. In other words: we still have a bogon...

Approved by: re@ (blanket)

END