From: "Michael S. Tsirkin" <mst@redhat.com>
To: Eric Auger <eric.auger@redhat.com>
Cc: eric.auger.pro@gmail.com, qemu-devel@nongnu.org,
qemu-arm@nongnu.org, jean-philippe@linaro.org,
alex.williamson@redhat.com, clg@redhat.com,
peter.maydell@linaro.org, Peter Xu <peterx@redhat.com>
Subject: Re: [PATCH v2] virtio-iommu: Use qemu_real_host_page_mask as default page_size_mask
Date: Tue, 13 Feb 2024 07:00:01 -0500 [thread overview]
Message-ID: <20240213064017-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <417ea71e-fb45-4e1d-b8e5-9d54d93dba3b@redhat.com>
On Tue, Feb 13, 2024 at 12:24:22PM +0100, Eric Auger wrote:
> Hi Michael,
> On 2/13/24 12:09, Michael S. Tsirkin wrote:
> > On Tue, Feb 13, 2024 at 11:32:13AM +0100, Eric Auger wrote:
> >> Do you have an other concern?
> > I also worry a bit about migrating between hosts with different
> > page sizes. Not with kvm I am guessing but with tcg it does work I think?
> I have never tried but is it a valid use case? Adding Peter in CC.
> > Is this just for vfio and vdpa? Can we limit this to these setups
> > maybe?
> I am afraid we know the actual use case too later. If the VFIO device is
> hotplugged we have started working with 4kB granule.
>
> The other way is to introduce a min_granule option as done for aw-bits.
> But it is heavier.
>
> Thanks
>
> Eric
> >
Let's say, if you are changing the default then we definitely want
a way to get the cmpatible behaviour for tcg.
So the compat machinery should be user-accessible too and documented.
--
MST
next prev parent reply other threads:[~2024-02-13 12:01 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-17 13:20 [PATCH v2] virtio-iommu: Use qemu_real_host_page_mask as default page_size_mask Eric Auger
2024-02-13 9:43 ` Michael S. Tsirkin
2024-02-13 10:32 ` Eric Auger
2024-02-13 11:07 ` Michael S. Tsirkin
2024-02-13 11:19 ` Eric Auger
2024-02-13 11:39 ` Michael S. Tsirkin
2024-02-13 11:49 ` Eric Auger
2024-02-13 11:09 ` Michael S. Tsirkin
2024-02-13 11:24 ` Eric Auger
2024-02-13 12:00 ` Michael S. Tsirkin [this message]
2024-02-21 10:41 ` Eric Auger
2024-02-21 11:31 ` Jean-Philippe Brucker
2024-02-21 12:45 ` Eric Auger
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=20240213064017-mutt-send-email-mst@kernel.org \
--to=mst@redhat.com \
--cc=alex.williamson@redhat.com \
--cc=clg@redhat.com \
--cc=eric.auger.pro@gmail.com \
--cc=eric.auger@redhat.com \
--cc=jean-philippe@linaro.org \
--cc=peter.maydell@linaro.org \
--cc=peterx@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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).