I've tracked this down to sys/miscfs/genfs/genfs_vnops.c rev 1.35:

	revision 1.35
	date: 2001/06/14 08:22:14;  author: chs;  state: Exp;  lines: +12 -11
	be sure to allocate dirty zeroed pages to cover blocks we allocate
	to resolve a write fault.  fixes PR 13201.
	also, be sure to allocate blocks for write faults to holes even if
	the page is already in memory.  fixes PR 13189.

Any ideas Chuck?

I wonder if this is in anyway related to the probles Nate Williams is
seeing in kern/13361 (ld to large file)?

Simon.
--
Simon Burge                            <simonb@wasabisystems.com>
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