From cf0ad23ce4dc68d0617b01cc5eefdd133f87cafc Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Sun, 25 Nov 2012 16:49:15 +0100 Subject: [PATCH] usb: fail usbdevice_create() when there is no USB bus Report an error instead of segfaulting when attaching a USB device to a machine with no USB busses: $ qemu-system-arm -machine vexpress-a9 \ -sd Fedora-17-armhfp-vexpress-mmcblk0.img \ -kernel vmlinuz-3.4.2-3.fc17.armv7hl \ -initrd initramfs-3.4.2-3.fc17.armv7hl.img \ -usbdevice disk:format=raw:test.img Note that the vexpress-a9 machine does not have a USB host controller. Reported-by: David Abdurachmanov Signed-off-by: Stefan Hajnoczi Signed-off-by: Gerd Hoffmann (cherry picked from commit c128d6a6d785eb9235a4f6dbd52f405ab8c60bee) Signed-off-by: Michael Roth --- hw/usb/bus.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/hw/usb/bus.c b/hw/usb/bus.c index b649360..1f73a52 100644 --- a/hw/usb/bus.c +++ b/hw/usb/bus.c @@ -585,6 +585,13 @@ USBDevice *usbdevice_create(const char *cmdline) return NULL; } + if (!bus) { + error_report("Error: no usb bus to attach usbdevice %s, " + "please try -machine usb=on and check that " + "the machine model supports USB", driver); + return NULL; + } + if (!f->usbdevice_init) { if (*params) { error_report("usbdevice %s accepts no params", driver);