From 6887f2191807c2b3eb7b20a61ba5d63c3695a95d Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Mon, 14 Dec 2015 09:21:23 +0100 Subject: [PATCH] ehci: make idt processing more robust Make ehci_process_itd return an error in case we didn't do any actual iso transfer because we've found no active transaction. That'll avoid ehci happily run in circles forever if the guest builds a loop out of idts. Signed-off-by: Gerd Hoffmann --- hw/usb/hcd-ehci.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c index 4e2161b..d07f228 100644 --- a/hw/usb/hcd-ehci.c +++ b/hw/usb/hcd-ehci.c @@ -1389,7 +1389,7 @@ static int ehci_process_itd(EHCIState *ehci, { USBDevice *dev; USBEndpoint *ep; - uint32_t i, len, pid, dir, devaddr, endp; + uint32_t i, len, pid, dir, devaddr, endp, xfers = 0; uint32_t pg, off, ptr1, ptr2, max, mult; ehci->periodic_sched_active = PERIODIC_ACTIVE; @@ -1479,9 +1479,10 @@ static int ehci_process_itd(EHCIState *ehci, ehci_raise_irq(ehci, USBSTS_INT); } itd->transact[i] &= ~ITD_XACT_ACTIVE; + xfers++; } } - return 0; + return xfers ? 0 : -1; } -- 1.8.3.1