| Message ID | 1351684477-12213-3-git-send-email-hdegoede@redhat.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/hw/usb/hcd-uhci.c b/hw/usb/hcd-uhci.c index 99ed063..1ef1db9 100644 --- a/hw/usb/hcd-uhci.c +++ b/hw/usb/hcd-uhci.c @@ -879,6 +879,11 @@ static int uhci_handle_td(UHCIState *s, UHCIQueue *q, uint32_t qh_addr, if (q == NULL) { USBDevice *dev = uhci_find_device(s, (td->token >> 8) & 0x7f); USBEndpoint *ep = usb_ep_get(dev, pid, (td->token >> 15) & 0xf); + + if (ep == NULL) { + return uhci_handle_td_error(s, td, td_addr, USB_RET_NODEV, + int_mask); + } q = uhci_queue_new(s, qh_addr, td, ep); } async = uhci_async_alloc(q, td_addr);
My recent uhci cleanup series has introduced a regression, where qemu sometimes crashes on a device disconnect. The problem is that the uhci code never checked for a device not / no longer existing, instead it was relying on usb_handle_packet accepting a NULL device. But since we now pass usb_handle_packet q->ep->dev, rather then just a local dev variable, we crash as q->ep == NULL due to the device no longer existing. This patch fixes this. Note that this patch also improves over the old behavior were we would: 1) create a queue for the device 2) create an async for the packet 3) have usb_handle_packet fail 4) destroy the async 5) wait for the queue to be idle for 32 frames 6) destroy the queue Which was rather sub-optimal. Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- hw/usb/hcd-uhci.c | 5 +++++ 1 file changed, 5 insertions(+)