From 54cdfe511219b8051046be55a6e156c4f08ff7ff Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Fri, 29 May 2020 09:22:24 +0200 Subject: [PATCH] usb-host: workaround libusb bug libusb seems to no allways call the completion callback for requests canceled (which it is supposed to do according to the docs). So add a limit to avoid qemu waiting forever. Tested-by: BALATON Zoltan Signed-off-by: Gerd Hoffmann Message-Id: <20200529072225.3195-1-kraxel@redhat.com> --- hw/usb/host-libusb.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c index e88db544bc..ad7ed8fb0c 100644 --- a/hw/usb/host-libusb.c +++ b/hw/usb/host-libusb.c @@ -972,6 +972,7 @@ fail: static void usb_host_abort_xfers(USBHostDevice *s) { USBHostRequest *r, *rtmp; + int limit = 100; QTAILQ_FOREACH_SAFE(r, &s->requests, next, rtmp) { usb_host_req_abort(r); @@ -982,6 +983,19 @@ static void usb_host_abort_xfers(USBHostDevice *s) memset(&tv, 0, sizeof(tv)); tv.tv_usec = 2500; libusb_handle_events_timeout(ctx, &tv); + if (--limit == 0) { + /* + * Don't wait forever for libusb calling the complete + * callback (which will unlink and free the request). + * + * Leaking memory here, to make sure libusb will not + * access memory which we have released already. + */ + QTAILQ_FOREACH_SAFE(r, &s->requests, next, rtmp) { + QTAILQ_REMOVE(&s->requests, r, next); + } + return; + } } }