From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olaf Hering <olaf@aepfle.de>
Subject: using GNTTABOP_transfer on hvm guests
Date: Fri, 24 Sep 2010 22:33:26 +0200
Message-ID: <20100924203326.GA10791@aepfle.de>
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While looking for more missing p2m_is_paging(p2mt) checks I noticed that
also the GNTTABOP_transfer code path may return GNTST_eagain if all code
paths get changed to verify the p2mt.
But can this really happen? Reading the comments for
MODPARM_rx_copy/MODPARM_rx_flip in drivers/xen/netfront/netfront.c
indicates that hvm guests will not use the GNTTABOP_transfer path.

Are there any possible users for GNTTABOP_transfer in a hvm guest?
Could xenpaging ever work for paravirtualized guests?

Olaf