From: Alex Williamson <alex.williamson@redhat.com>
To: Steven Sistare <steven.sistare@oracle.com>
Cc: kvm@vger.kernel.org, Cornelia Huck <cohuck@redhat.com>,
Kirti Wankhede <kwankhede@nvidia.com>
Subject: Re: [PATCH V3 0/9] vfio virtual address update
Date: Mon, 1 Feb 2021 13:23:18 -0700 [thread overview]
Message-ID: <20210201132318.36795807@omen.home.shazbot.org> (raw)
In-Reply-To: <29f7a496-f3c5-c273-538a-34ae87215e0c@oracle.com>
On Sat, 30 Jan 2021 11:54:03 -0500
Steven Sistare <steven.sistare@oracle.com> wrote:
> On 1/29/2021 4:55 PM, Alex Williamson wrote:
> > On Fri, 29 Jan 2021 08:54:03 -0800
> > Steve Sistare <steven.sistare@oracle.com> wrote:
> >
> >> Add interfaces that allow the underlying memory object of an iova range
> >> to be mapped to a new virtual address in the host process:
> >>
> >> - VFIO_DMA_UNMAP_FLAG_VADDR for VFIO_IOMMU_UNMAP_DMA
> >> - VFIO_DMA_MAP_FLAG_VADDR flag for VFIO_IOMMU_MAP_DMA
> >> - VFIO_UPDATE_VADDR for VFIO_CHECK_EXTENSION
> >> - VFIO_DMA_UNMAP_FLAG_ALL for VFIO_IOMMU_UNMAP_DMA
> >> - VFIO_UNMAP_ALL for VFIO_CHECK_EXTENSION
> >>
> >> Unmap-vaddr invalidates the host virtual address in an iova range and blocks
> >> vfio translation of host virtual addresses, but DMA to already-mapped pages
> >> continues. Map-vaddr updates the base VA and resumes translation. The
> >> implementation supports iommu type1 and mediated devices. Unmap-all allows
> >> all ranges to be unmapped or invalidated in a single ioctl, which simplifies
> >> userland code.
> >>
> >> This functionality is necessary for live update, in which a host process
> >> such as qemu exec's an updated version of itself, while preserving its
> >> guest and vfio devices. The process blocks vfio VA translation, exec's
> >> its new self, mmap's the memory object(s) underlying vfio object, updates
> >> the VA, and unblocks translation. For a working example that uses these
> >> new interfaces, see the QEMU patch series "[PATCH V2] Live Update" at
> >> https://lore.kernel.org/qemu-devel/1609861330-129855-1-git-send-email-steven.sistare@oracle.com
> >>
> >> Patches 1-3 define and implement the flag to unmap all ranges.
> >> Patches 4-6 define and implement the flags to update vaddr.
> >> Patches 7-9 add blocking to complete the implementation.
> >
> > Hi Steve,
> >
> > It looks pretty good to me, but I have some nit-picky comments that
> > I'll follow-up with on the individual patches. However, I've made the
> > changes I suggest in a branch that you can find here:
> >
> > git://github.com/awilliam/linux-vfio.git vaddr-v3
> >
> > If the changes look ok, just send me an ack, I don't want to attribute
> > something to you that you don't approve of. Thanks,
>
> All changes look good, thanks!
> Do you need anything more from me on this patch series?
Here's a new branch:
git://github.com/awilliam/linux-vfio.git vaddr-v3.1
Extent of the changes are s/may not/cannot/ on patches 1 & 4 and
addition of Connie's R-b for all (rebased to rc6). If there are any
final comments, speak now. Thanks,
Alex
next prev parent reply other threads:[~2021-02-01 20:25 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-29 16:54 [PATCH V3 0/9] vfio virtual address update Steve Sistare
2021-01-29 16:54 ` [PATCH V3 1/9] vfio: option to unmap all Steve Sistare
2021-02-01 11:42 ` Cornelia Huck
2021-02-01 12:52 ` Steven Sistare
2021-02-01 13:13 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 2/9] vfio/type1: unmap cleanup Steve Sistare
2021-02-01 11:50 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 3/9] vfio/type1: implement unmap all Steve Sistare
2021-02-01 11:59 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 4/9] vfio: interfaces to update vaddr Steve Sistare
2021-02-01 13:13 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 5/9] vfio/type1: massage unmap iteration Steve Sistare
2021-01-29 21:56 ` Alex Williamson
2021-01-30 16:51 ` Steven Sistare
2021-02-01 12:11 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 6/9] vfio/type1: implement interfaces to update vaddr Steve Sistare
2021-01-29 21:56 ` Alex Williamson
2021-01-30 16:51 ` Steven Sistare
2021-02-01 12:27 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 7/9] vfio: iommu driver notify callback Steve Sistare
2021-01-29 21:57 ` Alex Williamson
2021-01-30 16:51 ` Steven Sistare
2021-02-01 12:34 ` Cornelia Huck
2021-02-01 12:52 ` Steven Sistare
2021-02-01 13:17 ` Cornelia Huck
2021-02-01 13:17 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 8/9] vfio/type1: implement " Steve Sistare
2021-02-01 12:40 ` Cornelia Huck
2021-01-29 16:54 ` [PATCH V3 9/9] vfio/type1: block on invalid vaddr Steve Sistare
2021-02-01 12:47 ` Cornelia Huck
2021-01-29 21:55 ` [PATCH V3 0/9] vfio virtual address update Alex Williamson
2021-01-29 22:14 ` Steven Sistare
2021-01-30 16:54 ` Steven Sistare
2021-02-01 20:23 ` Alex Williamson [this message]
2021-02-01 21:13 ` Steven Sistare
2021-02-02 7:54 ` Cornelia Huck
2021-02-02 17:21 ` Alex Williamson
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