Reply-To: Gavin Shan <gshan@redhat.com>
Subject: Re: [PATCH v3 2/4] KVM: arm64: Add helper vgic_write_guest_lock()
To:     Zenghui Yu <zenghui.yu@linux.dev>, kvmarm@lists.linux.dev
Cc:     kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, pbonzini@redhat.com,
        corbet@lwn.net, maz@kernel.org, james.morse@arm.com,
        suzuki.poulose@arm.com, oliver.upton@linux.dev,
        yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org,
        yuzhe@nfschina.com, isaku.yamahata@intel.com, seanjc@google.com,
        ricarkol@google.com, eric.auger@redhat.com, renzhengeek@gmail.com,
        reijiw@google.com, shan.gavin@gmail.com
References: <20230126235451.469087-1-gshan@redhat.com>
 <20230126235451.469087-3-gshan@redhat.com>
 <a4b3ee35-a0d7-80f6-c64f-f9056c5b6110@linux.dev>
From:   Gavin Shan <gshan@redhat.com>
Message-ID: <9a8260b1-15f9-f8c9-34a7-0cce8e62a386@redhat.com>
Date:   Sat, 28 Jan 2023 10:33:09 +1100
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Hi Zenghui,

On 1/28/23 2:57 AM, Zenghui Yu wrote:
> [ just coming back from holiday, sorry for the late reply ]
> 

Hope you have a nice refresh. Thanks for your review.

> On 2023/1/27 07:54, Gavin Shan wrote:
>> Currently, the unknown no-running-vcpu sites are reported when a
>> dirty page is tracked by mark_page_dirty_in_slot(). Until now, the
>> only known no-running-vcpu site is saving vgic/its tables through
>> KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} command on KVM device
>> "kvm-arm-vgic-its". Unfortunately, there are more unknown sites to
>> be handled and no-running-vcpu context will be allowed in these
>> sites: (1) KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} command
>> on KVM device "kvm-arm-vgic-its" to restore vgic/its tables. The
>> vgic3 LPI pending status could be restored. (2) Save vgic3 pending
> 
> We typically write it as "VGICv3".
> 

Ok. I will fix by replacing 'vgic3' with 'VGICv3' in v4. However, the
term 'vgic/its' will be kept.

>> table through KVM_DEV_ARM_{VGIC_GRP_CTRL, VGIC_SAVE_PENDING_TABLES}
>> command on KVM device "kvm-arm-vgic-v3".
>>
>> In order to handle those unknown cases, we need a unified helper
>> vgic_write_guest_lock(). struct vgic_dist::save_its_tables_in_progress
>> is also renamed to struct vgic_dist::save_tables_in_progress.
> 
> How about renaming it to 'write_tables_in_progress' which would look a
> bit more generic? The rest looks good to me.
> 

'write_tables_in_progress' works for me. I will have it in v4, which
will be posted shortly.

Thanks,
Gavin