Commit 54cdfe51 authored by Gerd Hoffmann's avatar Gerd Hoffmann
Browse files

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: default avatarBALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
Message-Id: <20200529072225.3195-1-kraxel@redhat.com>
parent 9f815e83

hw/usb/host-libusb.c

+14 −0
Original line number Diff line number Diff line
@@ -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;

        }

    }

}