Save per cpu IDT information into the VMCS host area.

Without this, we may be saving the IDT info from the wrong cpu into the
vmcs.
This makes domU work in the presence of VMX domains on SMP/HT enabled
machines.

Signed-off-by: Chengyuan Li <chengyuan.li@intel.com>
Signed-off-by: Xiaofeng Ling <xiaofeng.ling@intel.com>=20
Signed-off-by: Arun Sharma <arun.sharma@intel.com>

xen/arch/x86/vmx_vmcs.c

@@ -190,10 +190,14 @@ void vmx_do_launch(struct vcpu *v)
 
     vmx_setup_platform(v, regs);
 
+    __asm__ __volatile__ ("sidt  (%0) \n" :: "a"(&desc) : "memory");
+    host_env.idtr_limit = desc.size;
+    host_env.idtr_base = desc.address;
+    error |= __vmwrite(HOST_IDTR_BASE, host_env.idtr_base);
+ 
     __asm__ __volatile__ ("sgdt  (%0) \n" :: "a"(&desc) : "memory");
     host_env.gdtr_limit = desc.size;
     host_env.gdtr_base = desc.address;
-
     error |= __vmwrite(HOST_GDTR_BASE, host_env.gdtr_base);
 
     error |= __vmwrite(GUEST_LDTR_SELECTOR, 0);
@@ -351,7 +355,6 @@ static inline int construct_vmcs_host(struct host_execution_env *host_env)
 {
     int error = 0;
     unsigned long crn;
-    struct Xgt_desc_struct desc;
 
     /* Host Selectors */
     host_env->ds_selector = __HYPERVISOR_DS;
@@ -377,14 +380,7 @@ static inline int construct_vmcs_host(struct host_execution_env *host_env)
     host_env->ds_base = 0;
     host_env->cs_base = 0;
 
-/* Debug */
-    __asm__ __volatile__ ("sidt  (%0) \n" :: "a"(&desc) : "memory");
-    host_env->idtr_limit = desc.size;
-    host_env->idtr_base = desc.address;
-    error |= __vmwrite(HOST_IDTR_BASE, host_env->idtr_base);
-
     __asm__ __volatile__ ("mov %%cr0,%0" : "=r" (crn) : );
-
     host_env->cr0 = crn;
     error |= __vmwrite(HOST_CR0, crn); /* same CR0 */
 
@@ -392,6 +388,7 @@ static inline int construct_vmcs_host(struct host_execution_env *host_env)
     __asm__ __volatile__ ("mov %%cr4,%0" : "=r" (crn) : ); 
     host_env->cr4 = crn;
     error |= __vmwrite(HOST_CR4, crn);
+
     error |= __vmwrite(HOST_RIP, (unsigned long) vmx_asm_vmexit_handler);
 #ifdef __x86_64__ 
     /* TBD: support cr8 for 64-bit guest */