From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Byrne <john.l.byrne@hp.com>
Subject: Live migration leaves page tables read-only?
Date: Tue, 28 Nov 2006 16:13:25 -0800
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I have been trying to debug a problem live-migrating SAP on Xen-3.0.3 
x86-64 (I also tested Xen-unstable changeset 12548) without success.

SAP seems to run fine on a given host; live-migrating it to another host 
causes the guest to almost immediately panic in the mprotect() call in 
the change_pte_range() routine in the set_pte_at() macro because the 
page table page it is trying to update is write-protected.

My attempts at understanding where this is coming from have come to 
naught. Any help in running this down would be appreciated. I am 
perfectly willing/able to write some debugging code if I am given a few 
clues what to look for.

Thanks,

John Byrne