[Qemu-devel] [PATCH] Register usb-uhci reset function.

[Gleb Natapov]

Update irq line on reset. Reseting irq line is required because
racing irq from pci device will call piix3_set_irq(). piix3_set_irq()
will remember current level in pci_irq_levels[]. The PIC line will be
triggered if one of pci_irq_levels[] is set (depends on piix3 config).
If for instance pci_irq_levels[0] and pci_irq_levels[1] are mapped to
the same PIC irq and during reset pci_irq_levels[1] == 1, but device
that drives pci_irq_levels[0] is initialized first the device driver
will not be able to lower irq line.

Without this patch RHEL4.8 hangs after reboot because usb interrupt
does not go away.

Signed-off-by: Gleb Natapov <address@hidden>
diff --git a/hw/usb-uhci.c b/hw/usb-uhci.c
index 689d40a..2db9850 100644
--- a/hw/usb-uhci.c
+++ b/hw/usb-uhci.c
@@ -346,6 +346,7 @@ static void uhci_reset(UHCIState *s)
     }
 
     uhci_async_cancel_all(s);
+    uhci_update_irq(s);
 }
 
 static void uhci_save(QEMUFile *f, void *opaque)
@@ -1093,6 +1094,7 @@ void usb_uhci_piix3_init(PCIBus *bus, int devfn)
     }
     s->frame_timer = qemu_new_timer(vm_clock, uhci_frame_timer, s);
 
+    qemu_register_reset(uhci_reset, 0, s);
     uhci_reset(s);
 
     /* Use region 4 for consistency with real hardware.  BSD guests seem
@@ -1127,6 +1129,7 @@ void usb_uhci_piix4_init(PCIBus *bus, int devfn)
     }
     s->frame_timer = qemu_new_timer(vm_clock, uhci_frame_timer, s);
 
+    qemu_register_reset(uhci_reset, 0, s);
     uhci_reset(s);
 
     /* Use region 4 for consistency with real hardware.  BSD guests seem
--
                        Gleb.