From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH v2 2/2] x86/hvm: Don't intercept #UD
 exceptions in general
Date: Thu, 28 Jan 2016 10:55:48 +0000
Message-ID: <56A9F3B4.5070406@citrix.com>
References: <56A91122.50502@oracle.com>
	<1453921984-29197-1-git-send-email-andrew.cooper3@citrix.com>
	<56A9F0B202000078000CBE78@prv-mh.provo.novell.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xen.org>
In-Reply-To: <56A9F0B202000078000CBE78@prv-mh.provo.novell.com>
List-Unsubscribe: <http://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <http://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Sender: xen-devel-bounces@lists.xen.org
Errors-To: xen-devel-bounces@lists.xen.org
To: Jan Beulich <JBeulich@suse.com>
Cc: Kevin Tian <kevin.tian@intel.com>, Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>, Xen-devel <xen-devel@lists.xen.org>, AravindGopalakrishnan <Aravind.Gopalakrishnan@amd.com>, Jun Nakajima <jun.nakajima@intel.com>, Boris Ostrovsky <boris.ostrovsky@oracle.com>
List-Id: xen-devel@lists.xenproject.org

On 28/01/16 09:42, Jan Beulich wrote:
>>>> On 27.01.16 at 20:13, <andrew.cooper3@citrix.com> wrote:
>> --- a/xen/arch/x86/hvm/svm/vmcb.c
>> +++ b/xen/arch/x86/hvm/svm/vmcb.c
>> @@ -192,6 +192,7 @@ static int construct_vmcb(struct vcpu *v)
>>  
>>      vmcb->_exception_intercepts =
>>          HVM_TRAP_MASK
>> +        | (opt_hvm_fep ? (1U << TRAP_invalid_op) : 0)
>>          | (1U << TRAP_no_device);
> This assumes a certain sequence of hypercalls by the tool stack
> (i.e. set-cpuid only after all vCPU-s got created, or else the
> intercept won't get enabled), which I think we should avoid.
> Instead I think you'd better call the new hook from
> hvm_vcpu_initialise().

Something like this (to be folded in) ?

andrewcoop@andrewcoop:/local/xen.git/xen$ git diff
diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 7a15d49..be5ead0 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -2484,6 +2484,8 @@ int hvm_vcpu_initialise(struct vcpu *v)
         hvm_set_guest_tsc(v, 0);
     }
 
+    hvm_update_guest_vendor(v);
+
     return 0;
 
  fail7:
diff --git a/xen/arch/x86/hvm/svm/vmcb.c b/xen/arch/x86/hvm/svm/vmcb.c
index be2dc32..9ea014f 100644
--- a/xen/arch/x86/hvm/svm/vmcb.c
+++ b/xen/arch/x86/hvm/svm/vmcb.c
@@ -192,7 +192,6 @@ static int construct_vmcb(struct vcpu *v)
 
     vmcb->_exception_intercepts =
         HVM_TRAP_MASK
-        | (opt_hvm_fep ? (1U << TRAP_invalid_op) : 0)
         | (1U << TRAP_no_device);
 
     if ( paging_mode_hap(v->domain) )
diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c
index a12813a..5bc3c74 100644
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -1237,7 +1237,6 @@ static int construct_vmcs(struct vcpu *v)
 
     v->arch.hvm_vmx.exception_bitmap = HVM_TRAP_MASK
               | (paging_mode_hap(d) ? 0 : (1U << TRAP_page_fault))
-              | (opt_hvm_fep ? (1U << TRAP_invalid_op) : 0)
               | (1U << TRAP_no_device);
     vmx_update_exception_bitmap(v);