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Date:   Mon, 19 Sep 2022 15:38:57 +0800
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Subject: Re: [RFC PATCH 0/9] kvm: implement atomic memslot updates
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To:     Emanuele Giuseppe Esposito <eesposit@redhat.com>,
        Sean Christopherson <seanjc@google.com>
Cc:     kvm@vger.kernel.org, Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        David Hildenbrand <david@redhat.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org,
        Maxim Levitsky <mlevitsk@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>
References: <20220909104506.738478-1-eesposit@redhat.com>
 <YxtOEgJhe4EcAJsE@google.com>
 <5f0345d2-d4d1-f4fe-86ba-6e22561cb6bd@redhat.com>
From:   Like Xu <like.xu.linux@gmail.com>
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On 19/9/2022 12:13 am, Emanuele Giuseppe Esposito wrote:
> 
> Am 09/09/2022 um 16:30 schrieb Sean Christopherson:
>> On Fri, Sep 09, 2022, Emanuele Giuseppe Esposito wrote:
>>> KVM is currently capable of receiving a single memslot update through
>>> the KVM_SET_USER_MEMORY_REGION ioctl.
>>> The problem arises when we want to atomically perform multiple updates,
>>> so that readers of memslot active list avoid seeing incomplete states.
>>>
>>> For example, in RHBZhttps://bugzilla.redhat.com/show_bug.cgi?id=1979276

Oh, thanks for stepping up to try to address it.

As it turns out, this issue was discovered "long" before
https://bugzilla.kernel.org/show_bug.cgi?id=213781

As a comment, relevant selftests are necessary and required.