[Xen-devel] [PATCH v3 4/4] x86/nvmx: update exit bitmap when using virtual interrupt delivery

[Roger Pau Monne <roger.pau@citrix.com>]

Force an update of the EOI exit bitmap in nvmx_update_apicv, because
the one performed in vmx_intr_assist might not be reached if the
interrupt is intercepted by nvmx_intr_intercept returning true.

Extract the code to update the exit bitmap from vmx_intr_assist into a
helper and use it in nvmx_update_apicv.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
---
Changes since v2:
 - Only update the EOI exit bitmap if GUEST_INTR_STATUS is changed.

Changes since v1:
 - Reword commit message.
---
 xen/arch/x86/hvm/vmx/intr.c       | 21 +++++++++++++--------
 xen/arch/x86/hvm/vmx/vvmx.c       |  3 +++
 xen/include/asm-x86/hvm/vmx/vmx.h |  2 ++
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/xen/arch/x86/hvm/vmx/intr.c b/xen/arch/x86/hvm/vmx/intr.c
index 49a1295f09..000e14af49 100644
--- a/xen/arch/x86/hvm/vmx/intr.c
+++ b/xen/arch/x86/hvm/vmx/intr.c
@@ -224,6 +224,18 @@ static int nvmx_intr_intercept(struct vcpu *v, struct hvm_intack intack)
     return 0;
 }
 
+void vmx_sync_exit_bitmap(struct vcpu *v)
+{
+    const unsigned int n = ARRAY_SIZE(v->arch.hvm.vmx.eoi_exit_bitmap);
+    unsigned int i;
+
+    while ( (i = find_first_bit(&v->arch.hvm.vmx.eoi_exitmap_changed, n)) < n )
+    {
+        clear_bit(i, &v->arch.hvm.vmx.eoi_exitmap_changed);
+        __vmwrite(EOI_EXIT_BITMAP(i), v->arch.hvm.vmx.eoi_exit_bitmap[i]);
+    }
+}
+
 void vmx_intr_assist(void)
 {
     struct hvm_intack intack;
@@ -318,7 +330,6 @@ void vmx_intr_assist(void)
               intack.source != hvm_intsrc_vector )
     {
         unsigned long status;
-        unsigned int i, n;
 
        /*
         * intack.vector is the highest priority vector. So we set eoi_exit_bitmap
@@ -379,13 +390,7 @@ void vmx_intr_assist(void)
                     intack.vector;
         __vmwrite(GUEST_INTR_STATUS, status);
 
-        n = ARRAY_SIZE(v->arch.hvm.vmx.eoi_exit_bitmap);
-        while ( (i = find_first_bit(&v->arch.hvm.vmx.eoi_exitmap_changed,
-                                    n)) < n )
-        {
-            clear_bit(i, &v->arch.hvm.vmx.eoi_exitmap_changed);
-            __vmwrite(EOI_EXIT_BITMAP(i), v->arch.hvm.vmx.eoi_exit_bitmap[i]);
-        }
+        vmx_sync_exit_bitmap(v);
 
         pt_intr_post(v, intack);
     }
diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c
index 39fb553590..452f69e2f7 100644
--- a/xen/arch/x86/hvm/vmx/vvmx.c
+++ b/xen/arch/x86/hvm/vmx/vvmx.c
@@ -1420,7 +1420,10 @@ static void nvmx_update_apicv(struct vcpu *v)
     }
 
     if ( status )
+    {
         __vmwrite(GUEST_INTR_STATUS, status);
+        vmx_sync_exit_bitmap(v);
+    }
 }
 
 static void virtual_vmexit(struct cpu_user_regs *regs)
diff --git a/xen/include/asm-x86/hvm/vmx/vmx.h b/xen/include/asm-x86/hvm/vmx/vmx.h
index b334e1ec94..111ccd7e61 100644
--- a/xen/include/asm-x86/hvm/vmx/vmx.h
+++ b/xen/include/asm-x86/hvm/vmx/vmx.h
@@ -610,6 +610,8 @@ void update_guest_eip(void);
 void vmx_pi_per_cpu_init(unsigned int cpu);
 void vmx_pi_desc_fixup(unsigned int cpu);
 
+void vmx_sync_exit_bitmap(struct vcpu *v);
+
 #ifdef CONFIG_HVM
 void vmx_pi_hooks_assign(struct domain *d);
 void vmx_pi_hooks_deassign(struct domain *d);
-- 
2.26.0