Panic with swap-backed md devices

[David Schultz]

On Sun, May 18, 2003, Giorgos Keramidas wrote:
> On 2003-05-17 22:35, David Schultz <das at FreeBSD.org> wrote:
> > On Thu, May 15, 2003, Giorgos Keramidas wrote:
> > > Trying to create and destroy a swap-backed md device results in panics
> > > with today's CURRENT.  I was trying to make a new -t swap md disk to
> > > test the problem described in a PR.  Using the following small shell
> > > script I noticed that it always causes a panic when mdconfig -d is run:
> > >
> > > 	mdconfig -a -t swap -s 100m -u 10
> > > 	disklabel -r -w md10 auto
> > > 	newfs -O 1 -b 8192 -s 1024 md10
> > > 	mount /dev/md10 /mnt
> > > 	mount
> > > 	umount /mnt
> > > 	mount
> > > 	mdconfig -d -u 10
> >
> > The following patch should fix the panic, but there's a small
> > vm_object leak that's still unfixed.  I'll look into that.
> 
> Thanks :)
> I'm CVSup'ing now and will build a kernel to test it in 1-2 hours.

Actually alc fixed it in src/sys/dev/md/md.c,v1.99, along with the
leak.  Apparently it's intentional that vm_pager_deallocate() is
not the inverse of vm_pager_allocate().  :-O