pcie/slot: fix hotplug event

When slot status register is cleared, PCIDevice::exp.hpev_notify
needs to be cleared.
Otherwise, PCIDevice::exp.hpev_notify is never set to false resulting
in no more hot plug event once it's raised.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/hw/pcie.c b/hw/pcie.c
index 39607bf31a..5c9eb2f0ac 100644
--- a/hw/pcie.c
+++ b/hw/pcie.c
@@ -175,6 +175,14 @@ static void hotplug_event_notify(PCIDevice *dev)
     }
 }
 
+static void hotplug_event_clear(PCIDevice *dev)
+{
+    hotplug_event_update_event_status(dev);
+    if (!msix_enabled(dev) && !msi_enabled(dev) && !dev->exp.hpev_notified) {
+        qemu_set_irq(dev->irq[dev->exp.hpev_intx], 0);
+    }
+}
+
 /*
  * A PCI Express Hot-Plug Event has occurred, so update slot status register
  * and notify OS of the event if necessary.
@@ -320,6 +328,10 @@ void pcie_cap_slot_write_config(PCIDevice *dev,
     uint8_t *exp_cap = dev->config + pos;
     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
 
+    if (ranges_overlap(addr, len, pos + PCI_EXP_SLTSTA, 2)) {
+        hotplug_event_clear(dev);
+    }
+
     if (!ranges_overlap(addr, len, pos + PCI_EXP_SLTCTL, 2)) {
         return;
     }