From: Avi Kivity <avi@redhat.com>
To: "Ira W. Snyder" <iws@ovro.caltech.edu>
Cc: Gregory Haskins <gregory.haskins@gmail.com>,
David Howells <dhowells@redhat.com>,
Gregory Haskins <ghaskins@novell.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
"alacrityvm-devel@lists.sourceforge.net"
<alacrityvm-devel@lists.sourceforge.net>
Subject: Re: [Alacrityvm-devel] [PATCH v2 2/4] KVM: introduce "xinterface" API for external interaction with guests
Date: Wed, 07 Oct 2009 09:43:30 +0200 [thread overview]
Message-ID: <4ACC46A2.2090103@redhat.com> (raw)
In-Reply-To: <20091006181859.GD6386@ovro.caltech.edu>
On 10/06/2009 08:18 PM, Ira W. Snyder wrote:
>
> The limitation I have is that memory made available from the host system
> (PCI card) as PCI BAR1 must not be migrated around in memory. I can only
> change the address decoding to hit a specific physical address. AFAIK,
> this means it cannot be userspace memory (since the underlying physical
> page could change, or it could be in swap), and must be allocated with
> something like __get_free_pages() or dma_alloc_coherent().
>
Expose it as /dev/something (/dev/mem, /sys/.../pci/...) and mmap() it,
and it becomes non-pageable user memory.
Not sure about dma_alloc_coherent(), that is meaningless on x86.
--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.
next prev parent reply other threads:[~2009-10-07 7:44 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-02 20:19 [PATCH v2 0/4] KVM: xinterface Gregory Haskins
2009-10-02 20:19 ` [PATCH v2 1/4] mm: export use_mm() and unuse_mm() to modules Gregory Haskins
2009-10-02 20:19 ` [PATCH v2 2/4] KVM: introduce "xinterface" API for external interaction with guests Gregory Haskins
2009-10-03 20:05 ` Marcelo Tosatti
2009-10-05 23:33 ` Gregory Haskins
2009-10-04 10:25 ` Avi Kivity
2009-10-05 23:57 ` Gregory Haskins
2009-10-06 9:34 ` Avi Kivity
2009-10-06 13:31 ` Gregory Haskins
2009-10-06 14:22 ` Gregory Haskins
2009-10-06 16:23 ` Avi Kivity
2009-10-06 17:00 ` Gregory Haskins
2009-10-06 17:00 ` Gregory Haskins
2009-10-06 19:40 ` Gregory Haskins
2009-10-07 8:11 ` Avi Kivity
2009-10-07 12:48 ` Gregory Haskins
2009-10-08 14:45 ` Avi Kivity
2009-10-06 16:19 ` Avi Kivity
2009-10-06 16:58 ` Gregory Haskins
2009-10-06 18:18 ` [Alacrityvm-devel] " Ira W. Snyder
2009-10-07 5:10 ` Amit Shah
2009-10-07 7:43 ` Avi Kivity [this message]
2009-10-02 20:19 ` [PATCH v2 3/4] KVM: add io services to xinterface Gregory Haskins
2009-10-04 10:26 ` Avi Kivity
2009-10-02 20:19 ` [PATCH v2 4/4] KVM: add scatterlist support " Gregory Haskins
2009-10-04 10:28 ` Avi Kivity
2009-10-05 23:57 ` Gregory Haskins
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4ACC46A2.2090103@redhat.com \
--to=avi@redhat.com \
--cc=alacrityvm-devel@lists.sourceforge.net \
--cc=dhowells@redhat.com \
--cc=ghaskins@novell.com \
--cc=gregory.haskins@gmail.com \
--cc=iws@ovro.caltech.edu \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).