From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Mon, 18 Aug 2014 23:24:27 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
MIME-Version: 1.0
To: David Matlack <dmatlack@google.com>,
	Xiao Guangrong <xiaoguangrong.eric@gmail.com>
CC: Gleb Natapov <gleb@kernel.org>, Avi Kivity <avi.kivity@gmail.com>,
	mtosatti@redhat.com, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH 1/2] KVM: fix cache stale memslot info with correct mmio
 generation number
References: <1407999713-3726-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> <53F20653.2030204@redhat.com> <9AD43423-2FF3-422D-A5AD-61CAE6339CCC@linux.vnet.ibm.com> <53F24A49.2010807@redhat.com> <A07DA8BD-8756-427D-9925-B8696E47C73A@gmail.com> <CALzav=fNoXeStA6ETDW0tNqyXBxWN0i8N5P-Ht7jtwgS_r7qmw@mail.gmail.com>
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Il 18/08/2014 23:15, David Matlack ha scritto:
> I just realized how simple Paolo's idea is. I think it can be a one line
> patch (without comments):
> 
> [...]
>         update_memslots(slots, new, kvm->memslots->generation);
>         rcu_assign_pointer(kvm->memslots, slots);
>         synchronize_srcu_expedited(&kvm->srcu);
> +       slots->generation++;
> 
>         kvm_arch_memslots_updated(kvm);
> [...]

Yeah, you're right.  I think at this point it makes sense to put all
generation handling in install_new_memslots, but with proper comments
the above can do as well.

Would you like to send it?  Patch 2 still applies on top.