From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41143) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a8RU1-0003R2-0k for qemu-devel@nongnu.org; Mon, 14 Dec 2015 06:40:06 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a8RTz-0001Ee-KP for qemu-devel@nongnu.org; Mon, 14 Dec 2015 06:40:00 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47650) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a8RTz-0001EC-FJ for qemu-devel@nongnu.org; Mon, 14 Dec 2015 06:39:59 -0500 From: Gerd Hoffmann Date: Mon, 14 Dec 2015 12:39:32 +0100 Message-Id: <1450093182-3500-2-git-send-email-kraxel@redhat.com> In-Reply-To: <1450093182-3500-1-git-send-email-kraxel@redhat.com> References: <1450093182-3500-1-git-send-email-kraxel@redhat.com> Subject: [Qemu-devel] [PATCH] ehci: make idt processing more robust List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: igvt-g@ml01.01.org, xen-devel@lists.xensource.com, Eduardo Habkost , Stefano Stabellini , Gerd Hoffmann , vfio-users@redhat.com 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