Subject: Re: cp(1) vs. UVM/UBC
To: Jason R Thorpe <>
From: Todd Vierling <>
List: tech-userlevel
Date: 07/22/2001 19:23:56
On Sun, 22 Jul 2001, Jason R Thorpe wrote:

:  > My point was that, regardless of what cp(1) uses, filesystems which can
:  > panic the system or break processes [where mmap(2) is broken under UBC] need
:  > to make mmap fail in those cases until the problems can be fixed.
: There is no way to make the mmap(2) call fail in those cases.

Check the filesystem against a known-bad (or known-good) list?  That's
~trivial to implement.

This is a hack, to be sure, but better a hack-until-UBC-works-on-them than a
panic or nondescript program failure.

-- Todd Vierling <>  *  Wasabi NetBSD:  Run with it.
-- NetBSD 1.5 now available on CD-ROM  --