>From 381eebe51657a3b3101dc80880fa3350dcfb1e23 Mon Sep 17 00:00:00 2001
From: Roger Pau Monne <roger.pau@xxxxxxxxxx>
Date: Thu, 19 Nov 2020 10:45:00 +0100
Subject: [PATCH]

---
 xen/arch/x86/hvm/vioapic.c   | 9 +++++++++
 xen/arch/x86/irq.c           | 3 +++
 xen/drivers/passthrough/io.c | 3 +++
 xen/include/asm-x86/irq.h    | 2 ++
 4 files changed, 17 insertions(+)

diff --git a/xen/arch/x86/hvm/vioapic.c b/xen/arch/x86/hvm/vioapic.c
index 67d4a6237f..1702434f0d 100644
--- a/xen/arch/x86/hvm/vioapic.c
+++ b/xen/arch/x86/hvm/vioapic.c
@@ -235,6 +235,10 @@ static void vioapic_write_redirent(
     pent = &vioapic->redirtbl[idx];
     ent  = *pent;
 
+    if ( gsi == TRACK_IRQ )
+        printk("vioapic write %s word %d val %#x current %#lx\n",
+               top_word ? "top" : "low", val, ent.bits);
+
     if ( top_word )
     {
         /* Contains only the dest_id. */
@@ -410,6 +414,9 @@ static void vioapic_deliver(struct hvm_vioapic *vioapic, unsigned int pin)
                 "vector=%x trig_mode=%x",
                 dest, dest_mode, delivery_mode, vector, trig_mode);
 
+    if ( irq == TRACK_IRQ )
+        printk("vioapic inject vector %#x\n", vector);
+
     switch ( delivery_mode )
     {
     case dest_LowestPrio:
@@ -517,6 +524,8 @@ void vioapic_update_EOI(struct domain *d, u8 vector)
                 continue;
 
             ent->fields.remote_irr = 0;
+            if ( vioapic->base_gsi + pin == TRACK_IRQ )
+                printk("vioapic EOI\n");
 
             if ( is_iommu_enabled(d) )
             {
diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
index 8d1f9a9fc6..34f50a24ea 100644
--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -1837,6 +1837,9 @@ static void do_IRQ_guest(struct irq_desc *desc, unsigned int vector)
     unsigned int        i;
     struct pending_eoi *peoi = this_cpu(pending_eoi);
 
+    if ( desc->irq == TRACK_IRQ )
+        printk("do_IRQ_guest\n");
+
     if ( unlikely(!action->nr_guests) )
     {
         /* An interrupt may slip through while freeing an ACKTYPE_EOI irq. */
diff --git a/xen/drivers/passthrough/io.c b/xen/drivers/passthrough/io.c
index 6b1305a3e5..ddbda10593 100644
--- a/xen/drivers/passthrough/io.c
+++ b/xen/drivers/passthrough/io.c
@@ -997,6 +997,9 @@ static void hvm_gsi_eoi(struct domain *d, unsigned int gsi,
     if ( !pirq_dpci(pirq) )
         return;
 
+    if ( gsi == TRACK_IRQ )
+        printk("dpci EOI\n");
+
     hvm_gsi_deassert(d, gsi);
     hvm_pirq_eoi(pirq, ent);
 }
diff --git a/xen/include/asm-x86/irq.h b/xen/include/asm-x86/irq.h
index 7c825e9d9c..bb450e5e59 100644
--- a/xen/include/asm-x86/irq.h
+++ b/xen/include/asm-x86/irq.h
@@ -218,4 +218,6 @@ int allocate_and_map_gsi_pirq(struct domain *d, int index, int *pirq_p);
 int allocate_and_map_msi_pirq(struct domain *d, int index, int *pirq_p,
                               int type, struct msi_info *msi);
 
+#define TRACK_IRQ 34
+
 #endif /* _ASM_HW_IRQ_H */
-- 
2.29.2