From mboxrd@z Thu Jan  1 00:00:00 1970
From: Valentine Sinitsyn <valentine.sinitsyn@gmail.com>
Subject: Re: Nested paging in nested SVM setup
Date: Thu, 21 Aug 2014 12:28:34 +0600
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References: <53A179C4.9060203@gmail.com> <53A18A6D.2050407@siemens.com> <53F44440.6070408@gmail.com> <53F44645.2000708@redhat.com> <53F45036.1070309@gmail.com> <53F45832.5080708@redhat.com>
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To: Paolo Bonzini <pbonzini@redhat.com>,
	Jan Kiszka <jan.kiszka@siemens.com>, kvm@vger.kernel.org
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Hi all,

On 20.08.2014 14:11, Paolo Bonzini wrote:
> Another patch...  I will post parts of it separately, if I am right
> you should get 0xfe as the vector and a WARN from the gva_to_gpa function.

With the patch like this:

> diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
> index 410776528265..cd91d03c9320 100644
> --- a/arch/x86/kvm/paging_tmpl.h
> +++ b/arch/x86/kvm/paging_tmpl.h
> @@ -365,8 +365,10 @@ retry_walk:
>  		gfn += pse36_gfn_delta(pte);
>
>  	real_gpa = mmu->translate_gpa(vcpu, gfn_to_gpa(gfn), access);
> 	if (real_gpa == UNMAPPED_GVA)
 > - 		return 0;
 > + 		goto error;
>
>  	walker->gfn = real_gpa >> PAGE_SHIFT;

KVM seems to work properly (no weird exceptions injected), although my 
code now freezes (quick look on the trace suggests it's looping reading 
APIC). Not sure whose bug is it, will look further.

Thanks for the help.

Valentine