From: Mark Brown <broonie@kernel.org>
To: Marc Zyngier <maz@kernel.org>
Cc: kernel-team@android.com, kvm@vger.kernel.org,
Will Deacon <will@kernel.org>,
kvmarm@lists.cs.columbia.edu,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 2/5] KVM: arm64: Get rid of host SVE tracking/saving
Date: Mon, 22 Nov 2021 17:58:00 +0000 [thread overview]
Message-ID: <YZvaKOLPxwFE9vQz@sirena.org.uk> (raw)
In-Reply-To: <871r38dvyr.wl-maz@kernel.org>
[-- Attachment #1.1: Type: text/plain, Size: 941 bytes --]
On Mon, Nov 22, 2021 at 03:57:32PM +0000, Marc Zyngier wrote:
> Zenghui Yu <yuzenghui@huawei.com> wrote:
> > Nit: This removes the only user of __sve_save_state() helper. Should we
> > still keep it in fpsimd.S?
> I was in two minds about that, as I'd like to eventually be able to
> use SVE for protected guests, where the hypervisor itself has to be in
> charge of the FP/SVE save-restore.
> But that's probably several months away, and I can always revert a
> deletion patch if I need to, so let's get rid of it now.
While we're on the subject of potential future work we might in future
want to not disable SVE on every syscall if (as seems likely) it turns
out that that's more performant for small vector lengths which would
mean some minor reshuffling here to do something like convert the saved
state to FPSIMD and drop TIF_SVE in _vcpu_load_fp(). As with using SVE
in protected guests that can just be done when needed though.
[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
[-- Attachment #2: Type: text/plain, Size: 151 bytes --]
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
next prev parent reply other threads:[~2021-11-22 17:58 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-28 11:16 [PATCH v2 0/5] KVM: arm64: Rework FPSIMD/SVE tracking Marc Zyngier
2021-10-28 11:16 ` [PATCH v2 1/5] KVM: arm64: Reorder vcpu flag definitions Marc Zyngier
2021-10-28 11:16 ` [PATCH v2 2/5] KVM: arm64: Get rid of host SVE tracking/saving Marc Zyngier
2021-10-28 13:02 ` Mark Brown
2021-11-10 13:19 ` Zenghui Yu
2021-11-22 15:57 ` Marc Zyngier
2021-11-22 17:58 ` Mark Brown [this message]
2021-11-22 18:10 ` Marc Zyngier
2021-11-22 18:30 ` Mark Brown
2021-11-23 10:11 ` Marc Zyngier
2021-11-23 12:33 ` Mark Brown
2021-10-28 11:16 ` [PATCH v2 3/5] KVM: arm64: Introduce flag shadowing TIF_FOREIGN_FPSTATE Marc Zyngier
2021-10-28 11:16 ` [PATCH v2 4/5] KVM: arm64: Stop mapping current thread_info at EL2 Marc Zyngier
2021-10-28 11:16 ` [PATCH v2 5/5] arm64/fpsimd: Document the use of TIF_FOREIGN_FPSTATE by KVM Marc Zyngier
2021-10-28 13:14 ` Mark Brown
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=YZvaKOLPxwFE9vQz@sirena.org.uk \
--to=broonie@kernel.org \
--cc=kernel-team@android.com \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=maz@kernel.org \
--cc=will@kernel.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