Xen devel - Jan 2013 - [PATCH v2 1/2] Xen: Fix live migration while enabling APICV

SVI should be restored in case guest is processing virtual interrupt
while saving a domain state. Otherwise SVI would be missed when
virtual interrupt delivery is enabled.

Signed-off-by: Jiongxi Li <jiongxi.li@intel.com>

diff --git a/xen/arch/x86/hvm/vlapic.c b/xen/arch/x86/hvm/vlapic.c
index ee2294c..801c4fa 100644
--- a/xen/arch/x86/hvm/vlapic.c
+++ b/xen/arch/x86/hvm/vlapic.c
@@ -1198,6 +1198,9 @@ static int lapic_load_regs(struct domain *d,
hvm_domain_context_t *h)
     if ( hvm_load_entry(LAPIC_REGS, h, s->regs) != 0 ) 
         return -EINVAL;
 
+    if ( hvm_funcs.set_svi )
+        hvm_funcs.set_svi(vlapic_find_highest_isr(s), v);
+
     vlapic_adjust_i8259_target(d);
     lapic_rearm(s);
     return 0;
diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 4d7c93f..2949782 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -1419,6 +1419,28 @@ static int vmx_virtual_intr_delivery_enabled(void)
     return cpu_has_vmx_virtual_intr_delivery;
 }
 
+static void vmx_set_svi(int isr, struct vcpu *v)
+{
+    unsigned long status;
+    u8 old;
+
+    if ( !cpu_has_vmx_virtual_intr_delivery )
+        return;
+
+    if (isr == -1)
+        isr = 0;
+
+    vmx_vmcs_enter(v);
+    status = __vmread(GUEST_INTR_STATUS);
+    old = status >> 8;
+    if (isr != old) {
+        status &= 0x0FF;
+        status |= isr << 8;
+        __vmwrite(GUEST_INTR_STATUS, status);
+    }
+    vmx_vmcs_exit(v);
+}
+
 static struct hvm_function_table __read_mostly vmx_function_table = {
     .name                 = "VMX",
     .cpu_up_prepare       = vmx_cpu_up_prepare,
@@ -1468,6 +1490,7 @@ static struct hvm_function_table __read_mostly
vmx_function_table = {
     .nhvm_domain_relinquish_resources = nvmx_domain_relinquish_resources,
     .update_eoi_exit_bitmap = vmx_update_eoi_exit_bitmap,
     .virtual_intr_delivery_enabled = vmx_virtual_intr_delivery_enabled,
+    .set_svi               = vmx_set_svi,
     .nhvm_hap_walk_L1_p2m = nvmx_hap_walk_L1_p2m,
 };
 
diff --git a/xen/include/asm-x86/hvm/hvm.h b/xen/include/asm-x86/hvm/hvm.h
index 76e9cc8..a0375a7 100644
--- a/xen/include/asm-x86/hvm/hvm.h
+++ b/xen/include/asm-x86/hvm/hvm.h
@@ -183,6 +183,7 @@ struct hvm_function_table {
     /* Virtual interrupt delivery */
     void (*update_eoi_exit_bitmap)(struct vcpu *v, u8 vector, u8 trig);
     int (*virtual_intr_delivery_enabled)(void);
+    void (*set_svi)(int isr, struct vcpu *v);
 
     /*Walk nested p2m  */
     int (*nhvm_hap_walk_L1_p2m)(struct vcpu *v, paddr_t L2_gpa,
-- 
1.7.1