From: Jason Gunthorpe <jgg@nvidia.com>
To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>
Cc: "Alex Williamson" <alex.williamson@redhat.com>,
"Avihai Horon" <avihaih@nvidia.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
"Juan Quintela" <quintela@redhat.com>,
"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
"Michael S. Tsirkin" <mst@redhat.com>,
"Cornelia Huck" <cohuck@redhat.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Vladimir Sementsov-Ogievskiy" <vsementsov@yandex-team.ru>,
"Cédric Le Goater" <clg@redhat.com>,
"Yishai Hadas" <yishaih@nvidia.com>,
"Maor Gottlieb" <maorg@nvidia.com>,
"Kirti Wankhede" <kwankhede@nvidia.com>,
"Tarun Gupta" <targupta@nvidia.com>,
"Joao Martins" <joao.m.martins@oracle.com>
Subject: Re: [PATCH v11 05/11] vfio/migration: Block multiple devices migration
Date: Tue, 16 May 2023 13:11:30 -0300 [thread overview]
Message-ID: <ZGOrMk1FPRH2/B3C@nvidia.com> (raw)
In-Reply-To: <a48c5d11dbcd470f93633aae721b2d18@huawei.com>
On Tue, May 16, 2023 at 02:35:21PM +0000, Shameerali Kolothum Thodi wrote:
> Ok. Got it. So it depends on what SMMU does for that mapping and is not
> related to migration per se and has the potential to crash the system if
> SMMU go ahead with that memory access. Isn't it a more generic problem
> then when we have multiple devices attached to the VM?
It is, and I am hoping to solve it when I get P2P support into iommufd
> I need to check if there is anything in SMMU spec that forbids this
> access.
There isn't, it is up to the integration how it handles 'hairpin'
traffic. A good implementation will work correctly as Intel and other
CPUs do. A very bad implementation will crash. Medium is to return
error tlps.
Jason
next prev parent reply other threads:[~2023-05-16 16:12 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-16 14:36 [PATCH v11 00/11] vfio/migration: Implement VFIO migration protocol v2 Avihai Horon
2023-02-16 14:36 ` [PATCH v11 01/11] linux-headers: Update to v6.2-rc8 Avihai Horon
2023-02-16 14:36 ` [PATCH v11 02/11] vfio/migration: Fix NULL pointer dereference bug Avihai Horon
2023-02-16 14:36 ` [PATCH v11 03/11] vfio/migration: Allow migration without VFIO IOMMU dirty tracking support Avihai Horon
2023-02-16 14:36 ` [PATCH v11 04/11] vfio/common: Change vfio_devices_all_running_and_saving() logic to equivalent one Avihai Horon
2023-02-16 14:53 ` Juan Quintela
2023-02-16 14:36 ` [PATCH v11 05/11] vfio/migration: Block multiple devices migration Avihai Horon
2023-05-16 10:03 ` Shameerali Kolothum Thodi via
2023-05-16 11:59 ` Jason Gunthorpe
2023-05-16 13:57 ` Shameerali Kolothum Thodi via
2023-05-16 14:04 ` Jason Gunthorpe
2023-05-16 14:27 ` Alex Williamson
2023-05-16 14:35 ` Shameerali Kolothum Thodi via
2023-05-16 16:11 ` Jason Gunthorpe [this message]
2023-02-16 14:36 ` [PATCH v11 06/11] vfio/migration: Move migration v1 logic to vfio_migration_init() Avihai Horon
2023-02-16 14:50 ` Juan Quintela
2023-02-16 14:36 ` [PATCH v11 07/11] vfio/migration: Rename functions/structs related to v1 protocol Avihai Horon
2023-02-16 14:54 ` Juan Quintela
2023-02-16 14:36 ` [PATCH v11 08/11] vfio/migration: Implement VFIO migration protocol v2 Avihai Horon
2023-02-16 15:43 ` Juan Quintela
2023-02-16 16:40 ` Avihai Horon
2023-02-16 16:52 ` Juan Quintela
2023-02-16 19:53 ` Alex Williamson
2024-09-04 13:00 ` Peter Xu
2024-09-04 15:41 ` Avihai Horon
2024-09-04 16:16 ` Peter Xu
2024-09-05 11:41 ` Avihai Horon
2024-09-05 15:17 ` Peter Xu
2024-09-05 16:07 ` Avihai Horon
2024-09-05 16:23 ` Peter Xu
2024-09-05 16:45 ` Avihai Horon
2024-09-05 18:31 ` Peter Xu
2024-09-09 12:52 ` Avihai Horon
2024-09-09 15:11 ` Peter Xu
2024-09-12 8:09 ` Avihai Horon
2024-09-12 9:41 ` Cédric Le Goater
2024-09-12 13:45 ` Peter Xu
2023-02-16 14:36 ` [PATCH v11 09/11] vfio/migration: Remove VFIO migration protocol v1 Avihai Horon
2023-02-16 14:36 ` [PATCH v11 10/11] vfio: Alphabetize migration section of VFIO trace-events file Avihai Horon
2023-02-16 14:36 ` [PATCH v11 11/11] docs/devel: Align VFIO migration docs to v2 protocol Avihai Horon
2023-02-16 14:57 ` Juan Quintela
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