Subject: Re: [PART1 RFC v3 02/12] KVM: x86: Introducing kvm_x86_ops VM
 init/uninit hooks
To: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>, rkrcmar@redhat.com,
        joro@8bytes.org, bp@alien8.de, gleb@kernel.org,
        alex.williamson@redhat.com
References: <1458281388-14452-1-git-send-email-Suravee.Suthikulpanit@amd.com>
 <1458281388-14452-3-git-send-email-Suravee.Suthikulpanit@amd.com>
 <56EBD438.5000702@redhat.com> <56FA1240.2000600@amd.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, wei@redhat.com,
        sherry.hurwitz@amd.com
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <56FA5737.2090406@redhat.com>
Date: Tue, 29 Mar 2016 12:21:43 +0200
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On 29/03/2016 07:27, Suravee Suthikulpanit wrote:
>>
>>> >Adding function pointers in struct kvm_x86_ops for processor-specific
>>> >layer to provide hooks for when KVM initialize and un-initialize VM.
>> This is not the only thing your patch is doing, and the "other" change
>> definitely needs a lot more explanation about why you did it and how you
>> audited the code to ensure that it is safe.
>>
>> Paolo
>>
> 
> Sorry, for not mentioning this earlier. I am moving the
> kvm_arch_init_vm() call mainly to go after mutex_init(&kvm->slots_lock)
> since I am calling the x86_set_memory_region() (which uses slots_lock)
> in the vm_init() hooks (for AVIC initialization).
> 
> Lemme re-check if this would be safe for other code.

No problem.  In the meanwhile a patch got in ("KVM: fix spin_lock_init
order on x86") that should help you.

Thanks,

Paolo