[Qemu-devel] [PATCH for-2.8] pci-assign: sync MSI/MSI-X cap and table with PCIDevice

[Peter Xu <peterx@redhat.com>]

Since commit e1d4fb2d ("kvm-irqchip: x86: add msi route notify fn"),
kvm_irqchip_add_msi_route() starts to use pci_get_msi_message() to fetch
MSI info. This requires that we setup MSI related fields in PCIDevice.
For most devices, that won't be a problem, as long as we are using
general interfaces like msi_init()/msix_init().

However, for pci-assign devices, MSI/MSI-X is treated differently - PCI
assign devices are maintaining its own MSI table and cap information in
AssignedDevice struct. however that's not synced up with PCIDevice's
fields. That will leads to pci_get_msi_message() failed to find correct
MSI capability, even with an NULL msix_table.

A quick fix is to sync up the two places: both the capability bits and
table address for MSI/MSI-X.

Reported-by: Changlimin <changlimin@h3c.com>
Cc: qemu-stable@nongnu.org
Fixes: e1d4fb2d ("kvm-irqchip: x86: add msi route notify fn")
Signed-off-by: Peter Xu <peterx@redhat.com>

---
Do we still support pci-assign?
---
 hw/i386/kvm/pci-assign.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
index 8238fbc..df9748d 100644
--- a/hw/i386/kvm/pci-assign.c
+++ b/hw/i386/kvm/pci-assign.c
@@ -1251,6 +1251,7 @@ static int assigned_device_pci_cap_init(PCIDevice *pci_dev, Error **errp)
             error_propagate(errp, local_err);
             return -ENOTSUP;
         }
+        dev->dev.cap_present |= QEMU_PCI_CAP_MSI;
         dev->cap.available |= ASSIGNED_DEVICE_CAP_MSI;
         /* Only 32-bit/no-mask currently supported */
         ret = pci_add_capability2(pci_dev, PCI_CAP_ID_MSI, pos, 10,
@@ -1285,6 +1286,7 @@ static int assigned_device_pci_cap_init(PCIDevice *pci_dev, Error **errp)
             error_propagate(errp, local_err);
             return -ENOTSUP;
         }
+        dev->dev.cap_present |= QEMU_PCI_CAP_MSIX;
         dev->cap.available |= ASSIGNED_DEVICE_CAP_MSIX;
         ret = pci_add_capability2(pci_dev, PCI_CAP_ID_MSIX, pos, 12,
                                   &local_err);
@@ -1648,6 +1650,7 @@ static void assigned_dev_register_msix_mmio(AssignedDevice *dev, Error **errp)
         dev->msix_table = NULL;
         return;
     }
+    dev->dev.msix_table = dev->msix_table;
 
     assigned_dev_msix_reset(dev);
 
@@ -1665,6 +1668,7 @@ static void assigned_dev_unregister_msix_mmio(AssignedDevice *dev)
         error_report("error unmapping msix_table! %s", strerror(errno));
     }
     dev->msix_table = NULL;
+    dev->dev.msix_table = NULL;
 }
 
 static const VMStateDescription vmstate_assigned_device = {
-- 
2.7.4