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Date:   Tue, 31 Oct 2023 09:43:32 -0700
From:   David Matlack <dmatlack@google.com>
To:     Sean Christopherson <seanjc@google.com>
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Subject: Re: [PATCH v13 13/35] KVM: Introduce per-page memory attributes
Message-ID: <ZUEutAmPcVLHXlQc@google.com>
References: <20231027182217.3615211-1-seanjc@google.com>
 <20231027182217.3615211-14-seanjc@google.com>
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On 2023-10-27 11:21 AM, Sean Christopherson wrote:
> From: Chao Peng <chao.p.peng@linux.intel.com>
> 
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 89c1a991a3b8..df573229651b 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -808,6 +809,9 @@ struct kvm {
>  
>  #ifdef CONFIG_HAVE_KVM_PM_NOTIFIER
>  	struct notifier_block pm_notifier;
> +#endif
> +#ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES
> +	struct xarray mem_attr_array;

Please document how access to mem_attr_array is synchronized. If I'm
reading the code correctly I think it's...

  /* Protected by slots_locks (for writes) and RCU (for reads) */