On Sat, 04 Apr 1998 12:49:05 -0000 (GMT) 
 jiho@postal.c-zone.net wrote:

 > Are pmap.c changes required JUST to install the new vfork(), or only if I want
 > to install UVM also?

You need it for vfork().

 > I think I just figured that out.  It's the allocation/deallocation of USPACE,
 > which has moved from a vmspace mapping to a kmem allocation, making the new
 > vfork() possible.  Correct?

No.  The new vfork() was made possible by sharing the "struct vmspace".

 > By the way, are you aware of any user programs that have had to be modified to
 > work with this shared vmspace vfork()?  David Brownlee keeps telling me he saw
 > a flurry of commits on the source-changes mailing list to that effect.  But I
 > don't see anything about it in CHANGES for -current (as of yesterday).

There were several programs in the tree, and a bug in the C library, that
violated the traditional "vfork rules" (which have existed since the
vfork in 3BSD, but which we got away with since 4.4BSD's vfork didn't
have the address space sharing semantics).

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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