From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH 5/24] Introduce vmcs12: a VMCS structure for L1
Date: Wed, 23 Jun 2010 12:24:41 +0300
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Cc: "Nadav Har'El" <nyh@math.technion.ac.il>, kvm@vger.kernel.org,
	Joerg Roedel <joerg.roedel@amd.com>
To: Alexander Graf <agraf@suse.de>
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On 06/23/2010 12:15 PM, Alexander Graf wrote:
>
>> Alex, Joerg, well gvmcb_{read,write}{32,64}() work for nsvm?  All that kmapping is incredibly annoying.
>>      
> I'm sceptical that we can actually get that to be as fast as a direct kmap, but apart from that I don't see an obvious reason why it wouldn't.
>    

I'm thinking of

struct kvm_cached_guest_page {
     void __user **pmem;
};

static u64 kvm_read_cached_guest_page(struct kvm_vcpu *vcpu, struct 
kvm_cached_guest_page *kcgp, unsigned offset)
{
     u64 __user *mem = *rcu_dereference(kcgp->kcgp) + offset;
     u64 ret;

     if (get_user(ret, mem))
         kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
     return ret;
}

We could even use our own exception handler to take the error case out 
of line.

-- 
error compiling committee.c: too many arguments to function