Re: port-xen/56782: panic: /: bad dir ino null entry

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Fri, 8 Apr 2022 09:38:22 +0200
    From:        Bartosz Maciejewski <bartosz%maciejewski.org@localhost>
    Message-ID:  <39d456e2-e694-8291-1072-e1913bd10e39%maciejewski.org@localhost>

  | Guest disk (one with problem). This is maximum disk size of 2TB that 
  | XCP-NG (Hypervisor/Domo) can create. There is still 0,5TB free space.

Actually, 2000 TiB which is not 2TB by anyone's reckoning (drive
manufacturers call 2TB 2 * 10^12 bytes, most of us, call it 2 * 2^40)
But that's irrelevant, its size is its size, and anything big enough
should work.   The free space is (for this purpose) even less relevant.

The data you provided would be easier to read if it wasn't full
of unpaddable spaces, seemingly cut & paste from some terminal
emulator, if there is a need for something like this again, it
would be better to, instead of ...

  | # dmesg | grep xbd

do

	cmesg | grep xbd >/tmp/file

and then simply add /tmp/file to the message (inserted, rather than
attached, if possible, but not cut&paste).


  | # disklabel xbd0

All of this looks OK.


  | # cat /etc/fstab

This one looks weird, but I suspect that's just an artifact of
the terminal emulator, and the cut & paste, as the df output shows
that the filesystems were mounted in their proper places, despite what
this file looks like as presented here.



  | Content of /run/sr-mount/f5c40583-1708-0f1d-cdfc-d3459226e19b 
  | (higlighted is NetBSD disk)

  | *-rw-r--r-- 1 root root 1580913943040 Apr  8 09:35 
  | 3d41c559-7edb-4fe7-8f98-bd50e21d0e3a.vhd*

That I believe was that one.   (The *'s or bold chars in the html version of
this message, as the highlighting indicated.)

That's very interesting.  The 2000 GiB should be 2147483648000 bytes
whereas that file is just 1580913943040 bytes (unless another cut&paste
misrepresentation has muddied the waters).

I will rewrite those numbers one above the other for easier comparison:

	2147483648000		NetBSD filesystem size (in bytes)
	1580913943040		.vhd file size (in bytes, I presume, it is just ls -l)

I know nothing of your Dom0 system, nor its virtual discs, nor how one
that is apparently just a bit less than 1500 GiB is able to appear in
NetBSD as being 2000 GiB big.

Note that it isn't even the full 'a' partition size, nor even close
enough to it to reach as far as the final cylinder group header (if
the file were only being allocated when space was actually touched,
more than this much should have been touched just by the newfs that
made the filesystem, before any data was even added).

None of the other files you showed in that listing look to be even
close to being big enough to hold the NetBSD filesystem.

But if all of this is as represented, this is very likely the cause of
the problems, but just how those actually occur, I am unable to say (I'd
guess something wrapping around in the file, somehow, but that would be
very very weird, very very buggy, and bizarre ... and nothing to do with
NetBSD.)


  | Hope this helps.

We need to see if this really is the issue, if it is, then yes, it
did, otherwise, perhaps not.

kre