XEN: pciback.hide disabled?

[Gilboa Davara]

On Thu, 2006-06-22 at 09:10 +1000, Gawain Lynch wrote:
> On Wed, 2006-06-21 at 21:29 +0300, Gilboa Davara wrote:
> > Hello all,
> > 
> > I'm trying to dedicate a number of NICs on a Xen setup to the guest OS.
> > It was advised (in the -users list) that I use the pciback.hide option
> > to hide the NICs from the host.
> > 
> > I tried adding the pciback.hide command line option to the Xen0 kernel
> > and got nothing. (Unknown boot option `pciback.hide=(xx:xx.x)':
> > ignoring)
> > After sifting through the kernel configuration I noticed that all FC5
> > xen kernels (including latest -testing) disable the PCIBACK support.
> > (CONFIG_XEN_PCIDEV_FRONTEND and CONFIG_XEN_PCIDEV_BACKEND)
> > 
> > Am I right? Do I need to enable these two to get pciback.hide working?
> > Or am I barking at the wrong tree?
> > 
> > Thanks,
> > Gilboa
> > 
> 
> See https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=188771
> 
> There are some issues with emabling it, including security
> considerations and it also breaks TCP checksums.  The latter can be
> fixed by running `ethtool -K eth0 tx off`
> 

Gawain,

Thanks for the link. I should have found it myself. 
/me club myself in the head for not googling for it...

I can't seem to find documentation of TCP checksum failure and/or
security issues.
Is it still true for recent (2.6.16/17) kernels?

Gilboa