Re: NetBSD domU ksyms issue under xen 4.1.6.1 and 4.2.3, not under 4.1.2

[Jeff Rizzo <riz%tastylime.net@localhost>]

On 10/15/13 5:05 PM, Jeff Rizzo wrote:
> I ran into a weird problem today that I'm still not 100% sure the root 
> cause of, and can use some additional ideas for what might be happening.
>
> I'm setting up a new dom0 host, a lovely 12-core box with 72G RAM; 
> it's running NetBSD 6.1.2/amd64 in dom0.  I launched a NetBSD 
> 6.1.2/amd64 domU, and noticed vmstat wasn't working:
>
> domU14# vmstat 1
> vmstat: undefined symbols: _allevents
> domU14#
>
> After some poking around, it looks like the symbol table as returned 
> by /dev/ksyms is slightly corrupted - some symbols (but not a lot!) 
> are missing.  Weird.
>
> I have another system (dom0 - the one I'm replacing with the new box) 
> with the same 6.1.2 domU image (I verified the md5), and the domU run 
> on this system does NOT exhibit the problem.
>
> Since the new box was running Xen 4.2.3 (binary pkg from 
> ftp.netbsd.org), and the old box Xen 4.1.2 (package I built myself a 
> year or two ago), I tried backing out to the Xen 4.1.6.1 package on 
> ftp.netbsd.org on the new box, and I got the same result.
>
> If, however, I tar up the xenkernel41 and xentools41 package from the 
> working system and install on the new box, the domU starts working as 
> expected!

a little more poking around reveals:

- it happens when loading the kernel directly too (not just via pygrub)
- it's related to the xentools package, not the kernel.  I was able to 
successfully use the 4.1.6.1 kernel with the 4.1.2 tools package. One 
other thing to note is the working package is based on python 2.6, the 
nonworking ones on 2.7.

+j