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Date:   Wed, 7 Apr 2021 21:57:02 +0100
From:   Will Deacon <will@kernel.org>
To:     Alexandru Elisei <alexandru.elisei@arm.com>
Cc:     Yanan Wang <wangyanan55@huawei.com>, Marc Zyngier <maz@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Gavin Shan <gshan@redhat.com>,
        Quentin Perret <qperret@google.com>,
        wanghaibin.wang@huawei.com, zhukeqian1@huawei.com,
        yuzenghui@huawei.com
Subject: Re: [RFC PATCH v3 1/2] KVM: arm64: Move CMOs from user_mem_abort to
 the fault handlers
Message-ID: <20210407205701.GA16198@willie-the-truck>
References: <20210326031654.3716-1-wangyanan55@huawei.com>
 <20210326031654.3716-2-wangyanan55@huawei.com>
 <cd6c8a86-b7b2-3d3e-121a-c9d1cb23c4b3@arm.com>
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On Wed, Apr 07, 2021 at 04:31:31PM +0100, Alexandru Elisei wrote:
> On 3/26/21 3:16 AM, Yanan Wang wrote:
> > We currently uniformly permorm CMOs of D-cache and I-cache in function
> > user_mem_abort before calling the fault handlers. If we get concurrent
> > guest faults(e.g. translation faults, permission faults) or some really
> > unnecessary guest faults caused by BBM, CMOs for the first vcpu are
> 
> I can't figure out what BBM means.

Oh, I know that one! BBM means "Break Before Make". Not to be confused with
DBM (Dirty Bit Management) or BFM (Bit Field Move).

Will