From: Jeremy Fitzhardinge <jeremy@goop.org>
To: Derek Murray <Derek.Murray@cl.cam.ac.uk>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>,
Eduardo Habkost <ehabkost@redhat.com>,
Juan Quintela <quintela@redhat.com>,
Jan Beulich <jbeulich@novell.com>,
Glauber de Oliveira Costa <gcosta@redhat.com>,
Chris Wright <chrisw@sous-sol.org>,
"virtualization@lists.osdl.org" <virtualization@lists.osdl.org>,
Gerd Hoffmann <kraxel@redhat.com>
Subject: Re: Re: Next steps with pv_ops for Xen
Date: Wed, 05 Dec 2007 10:12:02 -0800 [thread overview]
Message-ID: <4756E9F2.4050502@goop.org> (raw)
In-Reply-To: <47569014.8080008@cl.cam.ac.uk>
Derek Murray wrote:
> Ultimately, fork calls dup_mm, which calls, dup_mmap, which calls
> copy_{page,pud,pmd,pte}_range, which calls copy_one_pte, which calls
> set_pte_at, which hypercalls HYPERVISOR_update_va_mapping.
>
> The hypercall will not succeed and will return an error code
> indicating the reason for this. Therefore the PTE will not be set.
> There appears to be no way to propagate this error through the Linux
> VM code, because there is no concept of a PTE update failing. I could
> add return codes to all those functions, but I don't fancy their
> chances upstream....
Could we use one of the software-defined bits in the PTE to indicate
that this is a foreign/granted PTE, and have set_pte_at behave
differently if you pass it a pte with this bit set?
J
next prev parent reply other threads:[~2007-12-05 18:12 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-21 22:05 Next steps with pv_ops for Xen Stephen C. Tweedie
2007-11-21 23:12 ` Jeremy Fitzhardinge
2007-11-26 14:02 ` Juan Quintela
2007-11-26 18:52 ` Jeremy Fitzhardinge
2007-11-27 8:30 ` Jan Beulich
2007-11-27 17:00 ` Jeremy Fitzhardinge
2007-11-27 17:14 ` Jan Beulich
2007-11-27 17:15 ` Stephen C. Tweedie
2007-12-03 12:54 ` Gerd Hoffmann
2007-12-03 13:19 ` Derek Murray
2007-12-03 14:16 ` Gerd Hoffmann
2007-12-03 14:51 ` Derek Murray
2007-12-03 17:18 ` Mark Williamson
2007-12-03 18:36 ` D.G. Murray
2007-12-03 19:08 ` Mark Williamson
2007-12-04 9:35 ` tgh
2007-12-05 3:42 ` Mark Williamson
2007-12-06 15:21 ` Gerd Hoffmann
2007-12-06 15:32 ` Derek Murray
2007-12-06 15:55 ` Gerd Hoffmann
2007-12-21 12:58 ` [Xen-devel] " Gerd Hoffmann
2007-12-03 20:38 ` Gerd Hoffmann
2007-12-04 9:40 ` Derek Murray
2007-12-04 12:01 ` Gerd Hoffmann
2007-12-04 12:39 ` Stephen C. Tweedie
2007-12-04 19:58 ` Gerd Hoffmann
2007-12-05 11:48 ` [Xen-devel] " Derek Murray
2007-12-05 13:19 ` Derek Murray
[not found] ` <47569014.8080008@cl.cam.ac.uk>
2007-12-05 14:12 ` Gerd Hoffmann
2007-12-05 14:22 ` Keir Fraser
2007-12-05 14:30 ` Derek Murray
2007-12-05 16:58 ` Keir Fraser
2007-12-05 17:17 ` Derek Murray
2007-12-05 17:22 ` Keir Fraser
2007-12-05 17:48 ` Derek Murray
2007-12-05 17:59 ` Keir Fraser
2007-12-05 18:15 ` Derek Murray
2007-12-12 8:27 ` Isaku Yamahata
2007-12-12 8:39 ` Keir Fraser
2007-12-12 8:44 ` Isaku Yamahata
2007-12-05 20:06 ` Gerd Hoffmann
2007-12-05 18:12 ` Jeremy Fitzhardinge [this message]
2007-12-05 18:29 ` Derek Murray
2007-12-05 20:15 ` Jeremy Fitzhardinge
2007-12-05 20:35 ` Geoffrey Lefebvre
2007-12-06 10:15 ` Gerd Hoffmann
2007-12-05 20:44 ` Keir Fraser
2007-12-06 10:00 ` Derek Murray
2007-12-06 19:55 ` [Xen-devel] " Jeremy Fitzhardinge
2007-12-05 10:03 ` Gerd Hoffmann
2007-12-05 12:51 ` Gerd Hoffmann
2007-12-05 10:11 ` Derek Murray
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