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Date:   Wed, 21 Dec 2022 13:34:38 +0000
From:   Mark Brown <broonie@kernel.org>
To:     Marc Zyngier <maz@kernel.org>
Cc:     Dong Bo <dongbo4@huawei.com>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
        kvmarm@lists.cs.columbia.edu,
        Nianyao Tang <tangnianyao@huawei.com>,
        James Morse <james.morse@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>
Subject: Re: [PATCH] KVM: arm64: Synchronize SMEN on vcpu schedule out
Message-ID: <Y6MLbsTpNI4E+5qe@sirena.org.uk>
References: <20221220105024.13484-1-dongbo4@huawei.com>
 <86v8m6bcuh.wl-maz@kernel.org>
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On Tue, Dec 20, 2022 at 10:15:18AM +0000, Marc Zyngier wrote:
> Dong Bo <dongbo4@huawei.com> wrote:

> > If we have VHE and need to reenable SME for host in
> > kvm_arch_vcpu_put_fp, CPACR.SMEN is modified from 0 to 1. Trap
> > control for reading SVCR is modified from enable to disable.
> > Synchronization is needed before reading SVCR later in
> > fpsimd_save, or it may cause sync exception which can not be
> > handled by host.

Reviewed-by: Mark Brown <broonie@kernel.org>

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