Re: iSCSI connection corrupts Xen block devices.

["Roger Pau Monné" <roger.pau@citrix.com>]

On 26/03/13 07:26, Dr. Greg Wettstein wrote:
> Hi, hope the week has started out well for everyone.
> 
> This report may be in the FWIW department since there may be a
> fundamental reason why this doesn't work.  We elected to report this
> to the Xen community since we thought any behavior which corrupted
> disk images needed to at least be reported.

Hello Greg,

I've also noticed this some time ago, the cause of this bug is that we
pass granted pages to netback, and when trying to perform the grant copy
operation it fails. I've sent a clumsy patch that solved the problem,
but it involves additional memcpy in order to avoid passing the granted
page to netback:

http://lists.xen.org/archives/html/xen-devel/2013-01/msg00717.html

The best solution I can think of is storing the grant frame reference
somewhere in the p2m table, and then using that reference instead of the
mfn when performing the grant copy operation.

Regards, Roger.