Re: Trouble getting xbd devices to work

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Sat, Aug 25, 2018 at 12:39:41PM +0200, Martin Husemann wrote:
> Hey folks,
> 
> I am trying to set a xen machine up and have some beginners trouble.
> I followed the howto quite cloesly and can fire up domUs now.
> 
> I have:
> 
> xentools48-4.8.3nb4
> xenkernel48-4.8.3
> 
> and NetBSD 8.99.24 (XEN3_DOM0) as dom0.
> 
> I tried two formats, one from the howto, another derived from the official
> xen config dokumentation. They look like this:
> 
> disk = [ '/dev/wd0f,raw,0x1,rw',
>          '/xen/NetBSD-8.0_STABLE-i386-install.img,,0x2,ro' ]
> 
> and
> 
> disk = [ 'phy:/dev/wd0g,0x1,w',
>          'file:/xen/NetBSD-8.0_STABLE-amd64-install.img,0x2,r' ]
> 
> Both seem to work fine from the dom0's PoV:
> 
> [ 1956.2051930] xbd backend: attach device wd0f (size 209715200) for domain 1
> [ 1956.2951925] xbd backend: attach device vnd0d (size 2662400) for domain 1
> 
> and
> 
> [ 4270.3217421] xbd backend: attach device wd0g (size 209715200) for domain 3
> [ 4270.4517413] xbd backend: attach device vnd0d (size 2867200) for domain 3
> 
> Disklabel for wd0 shows:
> 
>  f: 209715200 1350570816     4.2BSD      0     0     0  # (Cyl. 1339852 - 1547902*)
>  g: 209715200 1560286016     4.2BSD      0     0     0  # (Cyl. 1547902*- 1755953*)
> 
> and the files are there:
> 
> -rw-r--r--  1 root  wheel  1468006400 Aug 23 00:19 /xen/NetBSD-8.0_STABLE-amd64-install.img
> -rw-r--r--  1 root  wheel  1363148800 Aug 23 02:20 /xen/NetBSD-8.0_STABLE-i386-install.img
> 
> But both domUs show:
> 
> [   2.0000246] xbd0d: error reading fsbn 0 (xbd0 bn 0; cn 0 tn 0 sn 0)
> [   2.0000246] xbd0: dos partition I/O error
> [   2.0200351] xbd1: dos partition I/O error
> [   2.0200351] xbd1d: error reading fsbn 0 (xbd1 bn 0; cn 0 tn 0 sn 0)
> 
> 
> I suppose I am doing something stupid?

Are you using a current kernel for the domU ?
atf tests are failing in a similar way (disklabel can't read sector 0),
I suspect it's caused by xbd_xenbus.c 1.84. I'm testing this theory
right now.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--