From: Mark Rutland <mark.rutland@arm.com>
To: Marc Zyngier <maz@kernel.org>
Cc: Mark Brown <broonie@kernel.org>,
Oliver Upton <oliver.upton@linux.dev>,
Joey Gouly <joey.gouly@arm.com>,
Catalin Marinas <catalin.marinas@arm.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Will Deacon <will@kernel.org>,
Paolo Bonzini <pbonzini@redhat.com>,
Jonathan Corbet <corbet@lwn.net>, Shuah Khan <shuah@kernel.org>,
Dave Martin <Dave.Martin@arm.com>, Fuad Tabba <tabba@google.com>,
linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH RFC v3 09/27] KVM: arm64: Factor SVE guest exit handling out into a function
Date: Wed, 22 Jan 2025 11:56:41 +0000 [thread overview]
Message-ID: <Z5Dc-WMu2azhTuMn@J2N7QTR9R3> (raw)
In-Reply-To: <86o6zzukwr.wl-maz@kernel.org>
On Wed, Jan 22, 2025 at 11:51:00AM +0000, Marc Zyngier wrote:
> On Fri, 17 Jan 2025 11:34:09 +0000, Mark Rutland <mark.rutland@arm.com> wrote:
> > The TL;DR summary is that it's not sufficient for kvm_arch_vcpu_put_fp()
> > to fix up ZCR_ELx. Either:
> >
> > * That needs to be fixed up while IRQs are masked, e.g. by
> > saving/restoring the host and guest ZCR_EL1 and/or ZCR_ELx values in
> > kvm_arch_vcpu_ctxflush_fp() and kvm_arch_vcpu_ctxsync_fp()
> >
> > * The lazy save logic in fpsimd_save_user_state() needs to handle KVM
> > explicitly, saving the guest's ZCR_EL1 and restoring the host's
> > ZCR_ELx.
> >
> > I think we need to fix that before we extend this logic for SME.
>
> So save/restore ZCR_ELx eagerly? If that's what it takes, let's do
> that now.
I believe that's sufficient; I'll go double-check and spin that now.
Mark.
next prev parent reply other threads:[~2025-01-22 11:58 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-20 16:46 [PATCH RFC v3 00/27] KVM: arm64: Implement support for SME in non-protected guests Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 01/27] arm64/fpsimd: Update FA64 and ZT0 enables when loading SME state Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 02/27] arm64/fpsimd: Decide to save ZT0 and streaming mode FFR at bind time Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 03/27] arm64/fpsimd: Check enable bit for FA64 when saving EFI state Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 04/27] arm64/fpsimd: Determine maximum virtualisable SME vector length Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 05/27] KVM: arm64: Introduce non-UNDEF FGT control Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 06/27] KVM: arm64: Pull ctxt_has_ helpers to start of sysreg-sr.h Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 07/27] KVM: arm64: Convert cpacr_clear_set() to a static inline Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 08/27] KVM: arm64: Move SVE state access macros after feature test macros Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 09/27] KVM: arm64: Factor SVE guest exit handling out into a function Mark Brown
2025-01-17 11:34 ` Mark Rutland
2025-01-17 12:37 ` Mark Brown
2025-01-22 11:51 ` Marc Zyngier
2025-01-22 11:56 ` Mark Rutland [this message]
2024-12-20 16:46 ` [PATCH RFC v3 10/27] KVM: arm64: Rename SVE finalization constants to be more general Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 11/27] KVM: arm64: Document the KVM ABI for SME Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 12/27] KVM: arm64: Define internal features " Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 13/27] KVM: arm64: Rename sve_state_reg_region Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 14/27] KVM: arm64: Store vector lengths in an array Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 15/27] KVM: arm64: Implement SME vector length configuration Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 16/27] KVM: arm64: Add definitions for SME control register Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 17/27] KVM: arm64: Support TPIDR2_EL0 Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 18/27] KVM: arm64: Support SMIDR_EL1 for guests Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 19/27] KVM: arm64: Support SME priority registers Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 20/27] KVM: arm64: Provide assembly for SME state restore Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 21/27] KVM: arm64: Support Z and P registers in streaming mode Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 22/27] KVM: arm64: Expose SME specific state to userspace Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 23/27] KVM: arm64: Context switch SME state for normal guests Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 24/27] KVM: arm64: Handle SME exceptions Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 25/27] KVM: arm64: Provide interface for configuring and enabling SME for guests Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 26/27] KVM: arm64: selftests: Add SME system registers to get-reg-list Mark Brown
2024-12-20 16:46 ` [PATCH RFC v3 27/27] KVM: arm64: selftests: Add SME to set_id_regs test 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=Z5Dc-WMu2azhTuMn@J2N7QTR9R3 \
--to=mark.rutland@arm.com \
--cc=Dave.Martin@arm.com \
--cc=broonie@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=corbet@lwn.net \
--cc=joey.gouly@arm.com \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.linux.dev \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=maz@kernel.org \
--cc=oliver.upton@linux.dev \
--cc=pbonzini@redhat.com \
--cc=shuah@kernel.org \
--cc=suzuki.poulose@arm.com \
--cc=tabba@google.com \
--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