From: Stefan Hajnoczi <stefanha@redhat.com>
To: Eric Auger <eric.auger@redhat.com>
Cc: fam@euphon.net, lvivier@redhat.com, cohuck@redhat.com,
qemu-devel@nongnu.org, mreitz@redhat.com,
alex.williamson@redhat.com, qemu-arm@nongnu.org,
kwolf@redhat.com, philmd@redhat.com, eric.auger.pro@gmail.com
Subject: Re: [PATCH v2 0/2] NVMe passthrough: Take into account host IOVA reserved regions
Date: Wed, 30 Sep 2020 10:23:17 +0100 [thread overview]
Message-ID: <20200930092317.GD201070@stefanha-x1.localdomain> (raw)
In-Reply-To: <20200929085550.30926-1-eric.auger@redhat.com>
[-- Attachment #1: Type: text/plain, Size: 1895 bytes --]
On Tue, Sep 29, 2020 at 10:55:48AM +0200, Eric Auger wrote:
> The current IOVA allocator allocates within the [0x10000, 1ULL << 39]
> window, without paying attention to the host IOVA reserved regions.
> This prevents NVMe passthtrough from working on ARM as the fixed
> IOVAs rapidly grow up to the MSI reserved region [0x8000000, 0x8100000]
> causing some VFIO MAP DMA failures. This series collects the usable
> IOVA regions using VFIO GET_INFO (this requires the host to support
> VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE) and rework the fixed and
> temporary IOVA allocators to avoid those latter.
>
> For the time being we do not change the arbitrary min/max IOVAs.
> In theory they could be dynamically determined but the kernel
> currently fails to expose some HW limitations described in the ACPI
> tables (such as PCI root complex Device Memory Address Size Limit).
> See kernel thread related to "[RFC 0/3] iommu: Reserved regions for
> IOVAs beyond dma_mask and iommu aperture" for more details:
> https://lkml.org/lkml/2020/9/28/1102
>
> Best Regards
>
> Eric
>
> This series can be found at:
> https://github.com/eauger/qemu/tree/nvme_resv_v2
>
> This was tested on ARM only.
>
> History:
> v1 -> v2:
> - remove "util/vfio-helpers: Dynamically compute the min/max IOVA" to
> relax the kernel dependency
> - Fix cabapbility enumeration loop
> - set s->usable_iova_ranges=NULL to avoid double free
> - handle possible u64 wrap
>
> Eric Auger (2):
> util/vfio-helpers: Collect IOVA reserved regions
> util/vfio-helpers: Rework the IOVA allocator to avoid IOVA reserved
> regions
>
> util/vfio-helpers.c | 129 +++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 123 insertions(+), 6 deletions(-)
>
> --
> 2.21.3
>
Thanks, applied to my block tree:
https://github.com/stefanha/qemu/commits/block
Stefan
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
prev parent reply other threads:[~2020-09-30 9:24 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-29 8:55 [PATCH v2 0/2] NVMe passthrough: Take into account host IOVA reserved regions Eric Auger
2020-09-29 8:55 ` [PATCH v2 1/2] util/vfio-helpers: Collect " Eric Auger
2020-09-29 8:55 ` [PATCH v2 2/2] util/vfio-helpers: Rework the IOVA allocator to avoid " Eric Auger
2020-09-29 15:59 ` Stefan Hajnoczi
2020-09-29 19:44 ` Auger Eric
2020-09-30 9:18 ` Stefan Hajnoczi
2020-09-30 9:23 ` Stefan Hajnoczi [this message]
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=20200930092317.GD201070@stefanha-x1.localdomain \
--to=stefanha@redhat.com \
--cc=alex.williamson@redhat.com \
--cc=cohuck@redhat.com \
--cc=eric.auger.pro@gmail.com \
--cc=eric.auger@redhat.com \
--cc=fam@euphon.net \
--cc=kwolf@redhat.com \
--cc=lvivier@redhat.com \
--cc=mreitz@redhat.com \
--cc=philmd@redhat.com \
--cc=qemu-arm@nongnu.org \
--cc=qemu-devel@nongnu.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.