From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 4/5] KVM: MMU: store generation-number into mmio spte
Date: Mon, 18 Mar 2013 12:19:12 +0100
Message-ID: <5146F830.1070602@redhat.com>
References: <51433D98.4050605@linux.vnet.ibm.com> <51433E43.60900@linux.vnet.ibm.com>
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Cc: Marcelo Tosatti <mtosatti@redhat.com>,
	Gleb Natapov <gleb@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
To: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
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Il 15/03/2013 16:29, Xiao Guangrong ha scritto:
> +/*
> + * spte bits of bit 3 ~ bit 11 are used as low 9 bits of
> + * generation, the bits of bits 52 ~ bit 61 are used as
> + * high 12 bits of generation.
> + */

High 10 bits.

How often does the generation number change?  Especially with Takuya's
patches, using just 10 bits for the generation might be enough and
simplifies the code.

Paolo