[PATCH v2 2/3] x86/msi: don't use cached address and data fields in msi_desc for dump_msi()

[Roger Pau Monne]

Instead compose a dummy MSI message just for the purpose of getting the
delivery attributes, which are the same for all messages.  Note that the
previous usage of the cached MSI message wasn't fetching the hardware MSI
fields either.

No functional change intended.

Signed-off-by: Roger Pau Monné <roger....@citrix.com>
---
 xen/arch/x86/msi.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/xen/arch/x86/msi.c b/xen/arch/x86/msi.c
index 6c11d76015fb..8efe41b1526c 100644
--- a/xen/arch/x86/msi.c
+++ b/xen/arch/x86/msi.c
@@ -1454,6 +1454,16 @@ void __init early_msi_init(void)
 static void cf_check dump_msi(unsigned char key)
 {
     unsigned int irq;
+    struct msi_msg msg = {};
+    uint32_t addr, data;
+
+    /*
+     * Compose a dummy msg message for the purpose of getting the delivery
+     * attributes.
+     */
+    msi_compose_msg(FIRST_DYNAMIC_VECTOR, NULL, &msg);
+    addr = msg.address_lo;
+    data = msg.data;
 
     printk("MSI information:\n");
 
@@ -1461,7 +1471,7 @@ static void cf_check dump_msi(unsigned char key)
     {
         struct irq_desc *desc = irq_to_desc(irq);
         const struct msi_desc *entry;
-        u32 addr, data, dest32;
+        uint32_t dest32;
         signed char mask;
         struct msi_attrib attr;
         unsigned long flags;
@@ -1495,8 +1505,6 @@ static void cf_check dump_msi(unsigned char key)
             break;
         }
 
-        data = entry->msg.data;
-        addr = entry->msg.address_lo;
         dest32 = entry->msg.dest32;
         attr = entry->msi_attrib;
         if ( entry->msi_attrib.type )
@@ -1512,8 +1520,7 @@ static void cf_check dump_msi(unsigned char key)
             mask = '?';
         printk(" %-6s%4u vec=%02x%7s%6s%3sassert%5s%7s"
                " dest=%08x mask=%d/%c%c/%c\n",
-               type, irq,
-               (data & MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT,
+               type, irq, desc->arch.vector,
                data & MSI_DATA_DELIVERY_LOWPRI ? "lowest" : "fixed",
                data & MSI_DATA_TRIGGER_LEVEL ? "level" : "edge",
                data & MSI_DATA_LEVEL_ASSERT ? "" : "de",
-- 
2.48.1