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Date:   Tue, 14 Jun 2022 16:29:20 +0200
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To:     Claudio Imbrenda <imbrenda@linux.ibm.com>, kvm@vger.kernel.org
Cc:     borntraeger@de.ibm.com, thuth@redhat.com, pasic@linux.ibm.com,
        david@redhat.com, linux-s390@vger.kernel.org,
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        mimu@linux.ibm.com, nrb@linux.ibm.com
References: <20220603065645.10019-1-imbrenda@linux.ibm.com>
From:   Janosch Frank <frankja@linux.ibm.com>
Subject: Re: [PATCH v11 00/19] KVM: s390: pv: implement lazy destroy for
 reboot
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On 6/3/22 08:56, Claudio Imbrenda wrote:
> Previously, when a protected VM was rebooted or when it was shut down,
> its memory was made unprotected, and then the protected VM itself was
> destroyed. Looping over the whole address space can take some time,
> considering the overhead of the various Ultravisor Calls (UVCs). This
> means that a reboot or a shutdown would take a potentially long amount
> of time, depending on the amount of used memory.
> 
> This patchseries implements a deferred destroy mechanism for protected
> guests. When a protected guest is destroyed, its memory can be cleared
> in background, allowing the guest to restart or terminate significantly
> faster than before.
> 
> There are 2 possibilities when a protected VM is torn down:
> * it still has an address space associated (reboot case)
> * it does not have an address space anymore (shutdown case)
> 

Please add patches 1-13 to devel for some CI coverage.
I'll try reviewing the remaining patches this week.