From: Stefan Hajnoczi <stefanha@gmail.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Pawel Moll <pawel.moll@arm.com>,
"Michael S. Tsirkin" <mst@redhat.com>,
virtualization <virtualization@lists.linux-foundation.org>,
Christian Borntraeger <borntraeger@de.ibm.com>,
Sasha Levin <levinsasha928@gmail.com>
Subject: Re: [RFC 7/11] virtio_pci: new, capability-aware driver.
Date: Wed, 11 Jan 2012 14:28:48 +0000 [thread overview]
Message-ID: <CAJSP0QWMBhsg9ExmTsDG7d32p=7tokCPpm5Z0DMAm2_ADvvb+g@mail.gmail.com> (raw)
In-Reply-To: <1326273019.23910.118.camel@pasglop>
On Wed, Jan 11, 2012 at 9:10 AM, Benjamin Herrenschmidt
<benh@kernel.crashing.org> wrote:
> On Wed, 2012-01-11 at 08:47 +0000, Stefan Hajnoczi wrote:
>>
>> This is also an opportunity to stop using CPU physical addresses in
>> the ring and instead perform DMA like a normal PCI device (use bus
>> addresses).
>
> Euh why ?
Because it's a paravirt hack that ends up hitting corner cases. It's
not possible to do virtio-pci passthrough under nested virtualization
unless we use an IOMMU. Imagine passing virtio-net from L0 into the
L2 guest (i.e. PCI-passthrough). If virtio-pci is really "PCI" this
should be possible but it's not when we use physical addresses instead
of bus addresses.
Stefan
next prev parent reply other threads:[~2012-01-11 14:28 UTC|newest]
Thread overview: 101+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-12-08 10:22 [PATCH 0/11] RFC: PCI using capabilitities Rusty Russell
2011-12-08 10:30 ` [RFC 1/11] virtio: use u32, not bitmap for struct virtio_device's features Rusty Russell
2011-12-08 10:31 ` [RFC 2/11] virtio: add support for 64 bit features Rusty Russell
2011-12-08 10:32 ` [PATCH 0/11] RFC: PCI using capabilitities Sasha Levin
2011-12-08 10:32 ` [RFC 3/11] pci: add pci_iomap_range Rusty Russell
2011-12-15 8:30 ` Michael S. Tsirkin
2011-12-16 1:56 ` Rusty Russell
2011-12-08 10:34 ` [RFC 4/11] virtio-pci: define layout for virtio vendor-specific capabilities Rusty Russell
2011-12-10 21:14 ` Sasha Levin
2011-12-08 10:35 ` [RFC 6/11] virtio_pci: move old defines to legacy, introduce new structure Rusty Russell
2011-12-08 10:38 ` [RFC 6/11] virtio_pci: don't use the legacy driver if we find the new PCI capabilities Rusty Russell
2011-12-10 21:18 ` Sasha Levin
2011-12-11 5:15 ` Rusty Russell
2011-12-11 9:37 ` Michael S. Tsirkin
2011-12-08 10:39 ` [RFC 7/11] virtio_pci: new, capability-aware driver Rusty Russell
2011-12-11 9:42 ` Michael S. Tsirkin
2011-12-11 22:45 ` Rusty Russell
2011-12-12 11:49 ` Michael S. Tsirkin
2011-12-12 18:10 ` Don Dutile
2011-12-16 1:58 ` Rusty Russell
2013-05-28 7:56 ` Michael S. Tsirkin
2013-05-29 1:17 ` Rusty Russell
2013-05-29 10:21 ` Michael S. Tsirkin
2013-05-30 2:17 ` Rusty Russell
2011-12-12 18:25 ` Michael S. Tsirkin
2011-12-13 2:21 ` Rusty Russell
2011-12-15 8:27 ` Michael S. Tsirkin
2011-12-16 1:50 ` Rusty Russell
2011-12-18 10:18 ` Michael S. Tsirkin
2011-12-19 6:06 ` Rusty Russell
2011-12-19 9:13 ` Michael S. Tsirkin
2011-12-19 11:08 ` Rusty Russell
2011-12-20 11:37 ` Michael S. Tsirkin
2011-12-21 0:33 ` Rusty Russell
2011-12-21 9:19 ` Michael S. Tsirkin
2012-01-10 17:03 ` Michael S. Tsirkin
2012-01-11 0:25 ` Rusty Russell
2012-01-11 1:48 ` Benjamin Herrenschmidt
2012-01-11 8:47 ` Stefan Hajnoczi
2012-01-11 9:10 ` Benjamin Herrenschmidt
2012-01-11 14:28 ` Stefan Hajnoczi [this message]
2012-01-11 15:39 ` Michael S. Tsirkin
2012-01-11 17:21 ` Stefan Hajnoczi
2012-01-11 18:34 ` Michael S. Tsirkin
2012-01-11 20:56 ` Benjamin Herrenschmidt
2012-01-11 20:46 ` Benjamin Herrenschmidt
2012-01-12 10:37 ` Stefan Hajnoczi
2012-01-11 10:21 ` Michael S. Tsirkin
2012-01-11 21:13 ` Benjamin Herrenschmidt
2012-01-11 22:13 ` Michael S. Tsirkin
2012-01-11 22:19 ` Benjamin Herrenschmidt
2012-01-11 22:56 ` Benjamin Herrenschmidt
2012-01-12 5:29 ` Michael S. Tsirkin
2012-01-12 6:13 ` Benjamin Herrenschmidt
2012-01-12 6:37 ` Michael S. Tsirkin
2012-01-12 2:01 ` Rusty Russell
2012-01-12 4:31 ` Benjamin Herrenschmidt
2012-01-12 6:09 ` Michael S. Tsirkin
2012-01-12 6:28 ` Benjamin Herrenschmidt
2012-01-12 6:51 ` Michael S. Tsirkin
2012-01-12 7:03 ` Benjamin Herrenschmidt
2012-01-12 6:00 ` Michael S. Tsirkin
2012-01-13 3:22 ` Rusty Russell
2012-01-11 13:30 ` Anthony Liguori
2012-01-11 15:12 ` Michael S. Tsirkin
2012-01-11 15:15 ` Anthony Liguori
2012-01-11 15:21 ` Michael S. Tsirkin
2012-01-11 15:28 ` Anthony Liguori
2012-01-11 15:45 ` Michael S. Tsirkin
2012-01-11 16:02 ` Anthony Liguori
2012-01-11 17:08 ` Michael S. Tsirkin
2012-01-11 19:42 ` Anthony Liguori
2012-01-11 20:14 ` Michael S. Tsirkin
2012-01-11 20:26 ` Anthony Liguori
2012-01-11 21:02 ` Benjamin Herrenschmidt
2012-01-11 22:02 ` Michael S. Tsirkin
2012-01-11 22:16 ` Benjamin Herrenschmidt
2012-01-12 1:42 ` Rusty Russell
2012-01-13 2:19 ` Michael S. Tsirkin
2012-01-13 2:32 ` Benjamin Herrenschmidt
2012-01-18 15:29 ` Michael S. Tsirkin
2012-01-22 22:53 ` Rusty Russell
2012-01-18 4:52 ` Rusty Russell
2012-01-11 21:58 ` Michael S. Tsirkin
2012-01-11 20:59 ` Benjamin Herrenschmidt
2012-01-11 20:51 ` Benjamin Herrenschmidt
2012-01-11 20:50 ` Benjamin Herrenschmidt
2012-01-12 1:35 ` Rusty Russell
2011-12-08 10:40 ` [RFC 8/11] virtio_pci: share structure between legacy and modern Rusty Russell
2011-12-08 10:41 ` [RFC 9/11] virtio_pci: share interrupt/notify handlers " Rusty Russell
2011-12-08 10:42 ` [RFC 10/11] virtio_pci: share virtqueue setup/teardown between modern and legacy driver Rusty Russell
2011-12-08 10:44 ` [RFC 11/11] virtio_pci: simplify common helpers Rusty Russell
2011-12-08 15:37 ` [PATCH 0/11] RFC: PCI using capabilitities Sasha Levin
[not found] ` <1323358657.32487.9.camel@lappy>
2011-12-09 6:17 ` Rusty Russell
2011-12-10 21:32 ` Sasha Levin
2011-12-11 9:05 ` Avi Kivity
2011-12-11 10:03 ` Sasha Levin
2011-12-11 12:30 ` Michael S. Tsirkin
2011-12-11 12:48 ` Sasha Levin
2011-12-11 12:47 ` Michael S. Tsirkin
2011-12-11 12:53 ` Sasha Levin
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