qemu-xen-trad: fix msi_translate with PV event delivery

When switching from msitranslate to straight msi we need to make sure
that we respect PV event delivery for the msi if the guest asked for it:

- completely disable MSI on the device in pt_disable_msi_translate;
- then enable MSI again (pt_msi_setup), mapping the correct pirq to it.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Rolu <rolu@roce.org>

diff --git a/hw/pass-through.c b/hw/pass-through.c
index 6e396e37f0eeb04760a9cd98be93f2b6f3b09774..304c438e832d1e7ebc7f263d84f398ad38ad5a32 100644 (file)
--- a/hw/pass-through.c
+++ b/hw/pass-through.c
@@ -3841,21 +3841,18 @@ static int pt_msgctrl_reg_write(struct pt_dev *ptdev,
                 PT_LOG("guest enabling MSI, disable MSI-INTx translation\n");
                 pt_disable_msi_translate(ptdev);
             }
-            else
+            /* Init physical one */
+            PT_LOG("setup msi for dev %x\n", pd->devfn);
+            if (pt_msi_setup(ptdev))
             {
-                /* Init physical one */
-                PT_LOG("setup msi for dev %x\n", pd->devfn);
-                if (pt_msi_setup(ptdev))
-                {
-                   /* We do not broadcast the error to the framework code, so
-                    * that MSI errors are contained in MSI emulation code and
-                    * QEMU can go on running.
-                    * Guest MSI would be actually not working.
-                    */
-                   *value &= ~PCI_MSI_FLAGS_ENABLE;
-                   PT_LOG("Warning: Can not map MSI for dev %x\n", pd->devfn);
-                   return 0;
-                }
+                /* We do not broadcast the error to the framework code, so
+                 * that MSI errors are contained in MSI emulation code and
+                 * QEMU can go on running.
+                 * Guest MSI would be actually not working.
+                 */
+                *value &= ~PCI_MSI_FLAGS_ENABLE;
+                PT_LOG("Warning: Can not map MSI for dev %x\n", pd->devfn);
+                return 0;
             }
             if (pt_msi_update(ptdev))
             {

diff --git a/hw/pt-msi.c b/hw/pt-msi.c
index 70c4023ba428345f87085b78b6a0dfbab78e4d65..73f737d00080740af9a17480636496ffe201598a 100644 (file)
--- a/hw/pt-msi.c
+++ b/hw/pt-msi.c
@@ -263,16 +263,8 @@ void pt_disable_msi_translate(struct pt_dev *dev)
     uint8_t e_device = 0;
     uint8_t e_intx = 0;
 
-    /* MSI_ENABLE bit should be disabed until the new handler is set */
-    msi_set_enable(dev, 0);
-
-    e_device = PCI_SLOT(dev->dev.devfn);
-    e_intx = pci_intx(dev);
-
-    if (xc_domain_unbind_pt_irq(xc_handle, domid, dev->msi->pirq,
-                                 PT_IRQ_TYPE_MSI_TRANSLATE, 0,
-                                 e_device, e_intx, 0))
-        PT_LOG("Error: Unbinding pt irq for MSI-INTx failed!\n");
+    pt_msi_disable(dev);
+    dev->msi->flags |= MSI_FLAG_UNINIT;
 
     if (dev->machine_irq)
     {
@@ -280,8 +272,6 @@ void pt_disable_msi_translate(struct pt_dev *dev)
                                        0, e_device, e_intx))
             PT_LOG("Error: Rebinding of interrupt failed!\n");
     }
-
-    dev->msi_trans_en = 0;
 }
 
 static int pt_msix_update_one(struct pt_dev *dev, int entry_nr)