From: Jason Gunthorpe <jgg@mellanox.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>,
Shahaf Shuler <shahafs@mellanox.com>,
Rob Miller <rob.miller@broadcom.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
"virtualization@lists.linux-foundation.org"
<virtualization@lists.linux-foundation.org>,
Netdev <netdev@vger.kernel.org>,
"Bie, Tiwei" <tiwei.bie@intel.com>,
"maxime.coquelin@redhat.com" <maxime.coquelin@redhat.com>,
"Liang, Cunming" <cunming.liang@intel.com>,
"Wang, Zhihong" <zhihong.wang@intel.com>,
"Wang, Xiao W" <xiao.w.wang@intel.com>,
"haotian.wang@sifive.com" <haotian.wang@sifive.com>,
"Zhu, Lingshan" <lingshan.zhu@intel.com>,
"eperezma@redhat.com" <eperezma@redhat.com>,
"lulu@redhat.com" <lulu@redhat.com>, Parav Pandit <parav@m>
Subject: Re: [PATCH 3/5] vDPA: introduce vDPA bus
Date: Tue, 21 Jan 2020 14:05:04 +0000 [thread overview]
Message-ID: <20200121140456.GA12330@mellanox.com> (raw)
In-Reply-To: <20200121031506-mutt-send-email-mst@kernel.org>
On Tue, Jan 21, 2020 at 03:15:43AM -0500, Michael S. Tsirkin wrote:
> > This sounds more flexible e.g driver may choose to implement static mapping
> > one through commit. But a question here, it looks to me this still requires
> > the DMA to be synced with at least commit here. Otherwise device may get DMA
> > fault? Or device is expected to be paused DMA during begin?
> >
> > Thanks
>
> For example, commit might switch one set of tables for another,
> without need to pause DMA.
I'm not aware of any hardware that can do something like this
completely atomically..
Any mapping change API has to be based around add/remove regions
without any active DMA (ie active DMA is a guest error the guest can
be crashed if it does this)
Jason
WARNING: multiple messages have this Message-ID (diff)
From: Jason Gunthorpe <jgg@mellanox.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>,
Shahaf Shuler <shahafs@mellanox.com>,
Rob Miller <rob.miller@broadcom.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
"virtualization@lists.linux-foundation.org"
<virtualization@lists.linux-foundation.org>,
Netdev <netdev@vger.kernel.org>,
"Bie, Tiwei" <tiwei.bie@intel.com>,
"maxime.coquelin@redhat.com" <maxime.coquelin@redhat.com>,
"Liang, Cunming" <cunming.liang@intel.com>,
"Wang, Zhihong" <zhihong.wang@intel.com>,
"Wang, Xiao W" <xiao.w.wang@intel.com>,
"haotian.wang@sifive.com" <haotian.wang@sifive.com>,
"Zhu, Lingshan" <lingshan.zhu@intel.com>,
"eperezma@redhat.com" <eperezma@redhat.com>,
"lulu@redhat.com" <lulu@redhat.com>,
Parav Pandit <parav@mellanox.com>,
"Tian, Kevin" <kevin.tian@intel.com>,
"stefanha@redhat.com" <stefanha@redhat.com>,
"rdunlap@infradead.org" <rdunlap@infradead.org>,
"hch@infradead.org" <hch@infradead.org>,
Ariel Adam <aadam@redhat.com>,
"jakub.kicinski@netronome.com" <jakub.kicinski@netronome.com>,
Jiri Pirko <jiri@mellanox.com>,
"hanand@xilinx.com" <hanand@xilinx.com>,
"mhabets@solarflare.com" <mhabets@solarflare.com>
Subject: Re: [PATCH 3/5] vDPA: introduce vDPA bus
Date: Tue, 21 Jan 2020 14:05:04 +0000 [thread overview]
Message-ID: <20200121140456.GA12330@mellanox.com> (raw)
In-Reply-To: <20200121031506-mutt-send-email-mst@kernel.org>
On Tue, Jan 21, 2020 at 03:15:43AM -0500, Michael S. Tsirkin wrote:
> > This sounds more flexible e.g driver may choose to implement static mapping
> > one through commit. But a question here, it looks to me this still requires
> > the DMA to be synced with at least commit here. Otherwise device may get DMA
> > fault? Or device is expected to be paused DMA during begin?
> >
> > Thanks
>
> For example, commit might switch one set of tables for another,
> without need to pause DMA.
I'm not aware of any hardware that can do something like this
completely atomically..
Any mapping change API has to be based around add/remove regions
without any active DMA (ie active DMA is a guest error the guest can
be crashed if it does this)
Jason
next prev parent reply other threads:[~2020-01-21 14:05 UTC|newest]
Thread overview: 141+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-16 12:42 [PATCH 0/5] vDPA support Jason Wang
2020-01-16 12:42 ` [PATCH 1/5] vhost: factor out IOTLB Jason Wang
2020-01-17 4:14 ` Randy Dunlap
2020-01-17 9:34 ` Jason Wang
2020-01-18 0:01 ` kbuild test robot
2020-01-18 0:01 ` kbuild test robot
2020-01-18 0:01 ` kbuild test robot
2020-01-18 0:40 ` kbuild test robot
2020-01-18 0:40 ` kbuild test robot
2020-01-18 0:40 ` kbuild test robot
2020-01-16 12:42 ` [PATCH 2/5] vringh: IOTLB support Jason Wang
2020-01-17 21:54 ` kbuild test robot
2020-01-17 21:54 ` kbuild test robot
2020-01-17 21:54 ` kbuild test robot
2020-01-17 22:33 ` kbuild test robot
2020-01-17 22:33 ` kbuild test robot
2020-01-17 22:33 ` kbuild test robot
2020-01-16 12:42 ` [PATCH 3/5] vDPA: introduce vDPA bus Jason Wang
2020-01-16 15:22 ` Jason Gunthorpe
2020-01-16 15:22 ` Jason Gunthorpe
2020-01-17 3:03 ` Jason Wang
2020-01-17 3:03 ` Jason Wang
2020-01-17 13:54 ` Jason Gunthorpe
2020-01-17 13:54 ` Jason Gunthorpe
2020-01-20 7:50 ` Jason Wang
2020-01-20 7:50 ` Jason Wang
2020-01-20 12:17 ` Michael S. Tsirkin
2020-01-20 12:17 ` Michael S. Tsirkin
2020-01-20 17:50 ` Jason Gunthorpe
2020-01-20 17:50 ` Jason Gunthorpe
2020-01-20 21:56 ` Michael S. Tsirkin
2020-01-20 21:56 ` Michael S. Tsirkin
2020-01-21 14:12 ` Jason Gunthorpe
2020-01-21 14:12 ` Jason Gunthorpe
2020-01-21 14:15 ` Michael S. Tsirkin
2020-01-21 14:15 ` Michael S. Tsirkin
2020-01-21 14:16 ` Jason Gunthorpe
2020-01-21 14:16 ` Jason Gunthorpe
2020-01-21 8:40 ` Tian, Kevin
2020-01-21 8:40 ` Tian, Kevin
2020-01-21 9:41 ` Jason Wang
2020-01-21 9:41 ` Jason Wang
2020-01-17 4:16 ` Randy Dunlap
2020-01-17 9:34 ` Jason Wang
2020-01-17 12:13 ` Michael S. Tsirkin
2020-01-17 13:52 ` Jason Wang
2020-01-17 14:12 ` Rob Miller via Virtualization
2020-01-19 9:07 ` Shahaf Shuler
2020-01-19 9:07 ` Shahaf Shuler
2020-01-19 9:59 ` Michael S. Tsirkin
2020-01-19 9:59 ` Michael S. Tsirkin
2020-01-20 8:44 ` Jason Wang
2020-01-20 8:44 ` Jason Wang
2020-01-20 12:09 ` Michael S. Tsirkin
2020-01-20 12:09 ` Michael S. Tsirkin
2020-01-21 3:32 ` Jason Wang
2020-01-21 3:32 ` Jason Wang
2020-01-20 8:43 ` Jason Wang
2020-01-20 8:43 ` Jason Wang
2020-01-20 17:49 ` Jason Gunthorpe
2020-01-20 17:49 ` Jason Gunthorpe
2020-01-20 20:51 ` Shahaf Shuler
2020-01-20 20:51 ` Shahaf Shuler
2020-01-20 21:25 ` Michael S. Tsirkin
2020-01-20 21:25 ` Michael S. Tsirkin
2020-01-20 21:47 ` Shahaf Shuler
2020-01-20 21:47 ` Shahaf Shuler
2020-01-20 21:59 ` Michael S. Tsirkin
2020-01-20 21:59 ` Michael S. Tsirkin
2020-01-21 6:01 ` Shahaf Shuler
2020-01-21 6:01 ` Shahaf Shuler
2020-01-21 7:57 ` Jason Wang
2020-01-21 7:57 ` Jason Wang
2020-01-21 14:07 ` Jason Gunthorpe
2020-01-21 14:07 ` Jason Gunthorpe
2020-01-21 14:16 ` Michael S. Tsirkin
2020-01-21 14:16 ` Michael S. Tsirkin
2020-01-20 21:48 ` Michael S. Tsirkin
2020-01-20 21:48 ` Michael S. Tsirkin
2020-01-21 4:00 ` Jason Wang
2020-01-21 4:00 ` Jason Wang
2020-01-21 5:47 ` Michael S. Tsirkin
2020-01-21 5:47 ` Michael S. Tsirkin
2020-01-21 8:00 ` Jason Wang
2020-01-21 8:00 ` Jason Wang
2020-01-21 8:15 ` Michael S. Tsirkin
2020-01-21 8:15 ` Michael S. Tsirkin
2020-01-21 8:35 ` Jason Wang
2020-01-21 8:35 ` Jason Wang
2020-01-21 11:09 ` Shahaf Shuler
2020-01-21 11:09 ` Shahaf Shuler
2020-01-22 6:36 ` Jason Wang
2020-01-22 6:36 ` Jason Wang
2020-01-21 14:05 ` Jason Gunthorpe [this message]
2020-01-21 14:05 ` Jason Gunthorpe
2020-01-21 14:17 ` Michael S. Tsirkin
2020-01-21 14:17 ` Michael S. Tsirkin
2020-01-22 6:18 ` Jason Wang
2020-01-22 6:18 ` Jason Wang
2020-01-20 8:19 ` Jason Wang
2020-01-20 8:19 ` Jason Wang
2020-01-16 12:42 ` [PATCH 4/5] virtio: introduce a vDPA based transport Jason Wang
2020-01-16 15:38 ` Jason Gunthorpe
2020-01-16 15:38 ` Jason Gunthorpe
2020-01-17 9:32 ` Jason Wang
2020-01-17 9:32 ` Jason Wang
2020-01-17 14:00 ` Jason Gunthorpe
2020-01-17 14:00 ` Jason Gunthorpe
2020-01-20 7:52 ` Jason Wang
2020-01-20 7:52 ` Jason Wang
2020-01-17 4:10 ` Randy Dunlap
2020-01-16 12:42 ` [PATCH 5/5] vdpasim: vDPA device simulator Jason Wang
2020-01-16 15:47 ` Jason Gunthorpe
2020-01-16 15:47 ` Jason Gunthorpe
2020-01-17 9:32 ` Jason Wang
2020-01-17 9:32 ` Jason Wang
2020-01-17 14:10 ` Jason Gunthorpe
2020-01-17 14:10 ` Jason Gunthorpe
2020-01-20 8:01 ` Jason Wang
2020-01-20 8:01 ` Jason Wang
2020-02-04 4:19 ` Jason Wang
2020-02-04 4:19 ` Jason Wang
2020-01-17 4:12 ` Randy Dunlap
2020-01-17 9:35 ` Jason Wang
2020-01-18 18:18 ` kbuild test robot
2020-01-18 18:18 ` kbuild test robot
2020-01-18 18:18 ` kbuild test robot
2020-01-28 3:32 ` Dan Carpenter
2020-01-28 3:32 ` Dan Carpenter
2020-01-28 3:32 ` Dan Carpenter
2020-01-28 3:32 ` Dan Carpenter
2020-02-04 4:07 ` Jason Wang
2020-02-04 4:07 ` Jason Wang
2020-02-04 8:21 ` Zhu Lingshan
2020-02-04 8:28 ` Jason Wang
2020-02-04 12:52 ` Jason Gunthorpe
2020-02-05 3:14 ` Jason Wang
2020-01-21 8:44 ` [PATCH 0/5] vDPA support Tian, Kevin
2020-01-21 8:44 ` Tian, Kevin
2020-01-21 9:39 ` Jason Wang
2020-01-21 9:39 ` Jason Wang
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