From owner-freebsd-hackers@freebsd.org  Sun Sep  6 16:14:20 2015
Return-Path: <owner-freebsd-hackers@freebsd.org>
Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 5F96F9CBBA3
 for <freebsd-hackers@mailman.ysv.freebsd.org>;
 Sun,  6 Sep 2015 16:14:20 +0000 (UTC)
 (envelope-from dieterbsd@gmail.com)
Received: from mail-ig0-x233.google.com (mail-ig0-x233.google.com
 [IPv6:2607:f8b0:4001:c05::233])
 (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits))
 (Client CN "smtp.gmail.com",
 Issuer "Google Internet Authority G2" (verified OK))
 by mx1.freebsd.org (Postfix) with ESMTPS id 30E6210F9
 for <freebsd-hackers@freebsd.org>; Sun,  6 Sep 2015 16:14:20 +0000 (UTC)
 (envelope-from dieterbsd@gmail.com)
Received: by igbni9 with SMTP id ni9so43799891igb.0
 for <freebsd-hackers@freebsd.org>; Sun, 06 Sep 2015 09:14:19 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113;
 h=mime-version:date:message-id:subject:from:to:content-type;
 bh=T79mkKEGfeLZr6sQe3HDkniLAt8Z7QyDz0U6rHJ9vPA=;
 b=jK745k9cIikaOCetJW85VysRpMo7BMBjUk/VJrT49OxljJ7SQ1AkqITBvtzu1O33M1
 r5zIw4jyPPwgQmy/tWMgoP/y/EC8Kkvtcw08LEofNJm84WOvtmBUmY6bMdu579olZEGZ
 W0nfFdt7/D4m4NEABYGpdCWKG2DMApTPtK+VYofwKcI65W/kJaF5zj7OY+pZmaqfXAxJ
 hgkBX293uUpveS0fbdIMbkhqqT4akzJFIxMMxBHgsGtcVxy+WvHQR7qdeXdXXlLh2yl3
 kd2C4jrn7H6DnY8OPKVyELb+dCyqp3V74hXqpdi1xgWSTv7hKjXZLlcAtnFioYTqJCZq
 5/pQ==
MIME-Version: 1.0
X-Received: by 10.50.111.83 with SMTP id ig19mr22283393igb.82.1441556059210;
 Sun, 06 Sep 2015 09:14:19 -0700 (PDT)
Received: by 10.64.2.132 with HTTP; Sun, 6 Sep 2015 09:14:19 -0700 (PDT)
Date: Sun, 6 Sep 2015 09:14:19 -0700
Message-ID: <CAA3ZYrCJKQqK1_zYLcPS3ZCLry2SFQ478zL+etNYrsSoL4nYbg@mail.gmail.com>
Subject: Re: Mount NetBSD partition/slice
From: Dieter BSD <dieterbsd@gmail.com>
To: freebsd-hackers@freebsd.org
Content-Type: text/plain; charset=UTF-8
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.20
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
 <freebsd-hackers.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-hackers>, 
 <mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers/>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, 
 <mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 06 Sep 2015 16:14:20 -0000

Don whY:
> A bit of research indicates that there is
> no support for these incompatible volume formats.

What, exactly, do you mean by  "volume formats"?

What type of media?  Some USB-to-[PS]ATA bridges have bugs
(or just plain brain damage) and sector(s) are missing.
This can prevent the OS from finding the partitioning info.
This can be worked around by hacking the kernel, but probably
doesn't qualify as the "least amount of wasted effort/time"
you are seeking.

What type of partitioning?  BSD disklabel? MBR? GPT? ...
What filesystem?

I have vanilla sata disks with a NetBSD mbr, and NetBSD 4.0
and 5.0.1 partitions ("slices" if you prefer),  FFS with softdep.
FreeBSD/amd64 6.x, 7.x and 8.x mount and read these partitions fine.
NetBSD 6.0 and newer would not have softdep.  FreeBSD 10.1 is broken.
NetBSD partitions on gpt disks also mount and read fine under
FreeBSD.