xemu-project/xemu
1
0
Fork 0
mirror of https://github.com/xemu-project/xemu.git synced 2025-02-17 18:48:36 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

usb: Suppress bogus error when automatic usb-hub creation fails

Browse Source 
USBDevice's realize method usb_qdev_realize() automatically creates a
usb-hub when only one port is left.  Creating devices in realize
methods is questionable, but works.

If usb-hub creation fails, an error is reported to stderr, but the
failure is otherwise ignored.  We then create the actual device using
the last port, which may well succeed.

Example:

    $ qemu -nodefaults -S -display none -machine usb=on -monitor stdio
    QEMU 2.2.50 monitor - type 'help' for more information
    (qemu) device_add usb-mouse
    [Repeat 36 times]
    (qemu) info usb
      Device 0.0, Port 1, Speed 12 Mb/s, Product QEMU USB Mouse
      Device 0.0, Port 2, Speed 12 Mb/s, Product QEMU USB Hub
      Device 0.0, Port 2.1, Speed 12 Mb/s, Product QEMU USB Mouse
    [More mice and hubs omitted...]
      Device 0.0, Port 2.8.8.8.8.7, Speed 12 Mb/s, Product QEMU USB Mouse
    (qemu) device_add usb-mouse
    usb hub chain too deep
    Failed to initialize USB device 'usb-hub'
    (qemu) info usb
    [...]
      Device 0.0, Port 2.8.8.8.8.7, Speed 12 Mb/s, Product QEMU USB Mouse
      Device 0.0, Port 2.8.8.8.8.8, Speed 12 Mb/s, Product QEMU USB Mouse

Despite the "Failed" message, the command actually succeeded.

In QMP, it's worse.  When adding the 37th mouse via QMP, the command
fails with

    {"error": {"class": "GenericError", "desc": "usb hub chain too deep"}}

Additionally, "Failed to initialize USB device 'usb-hub'" is reported
on stderr.  Despite the command failure, the device was created.  This
is wrong.

Fix by avoiding qdev_init() for usb-hub creation, so we can ignore
errors cleanly.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Markus Armbruster 2015-02-04 13:28:11 +01:00 committed by Gerd Hoffmann
parent 06f22eb78f
commit bd8b92d5c8
1 changed files with 28 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
hw/usb/bus.c
View File

@ -315,15 +315,36 @@ USBDevice *usb_create(USBBus *bus, const char *name)
return USB_DEVICE(dev);
}
static USBDevice *usb_try_create_simple(USBBus *bus, const char *name,
Error **errp)
{
Error *err = NULL;
USBDevice *dev;
dev = USB_DEVICE(qdev_try_create(&bus->qbus, name));
if (!dev) {
error_setg(errp, "Failed to create USB device '%s'", name);
return NULL;
}
object_property_set_bool(OBJECT(dev), true, "realized", &err);
if (err) {
error_setg(errp, "Failed to initialize USB device '%s': %s",
name, error_get_pretty(err));
error_free(err);
object_unparent(OBJECT(dev));
return NULL;
}
return dev;
}
USBDevice *usb_create_simple(USBBus *bus, const char *name)
{
USBDevice *dev = usb_create(bus, name);
int rc;
Error *err = NULL;
USBDevice *dev = usb_try_create_simple(bus, name, &err);
rc = qdev_init(&dev->qdev);
if (rc < 0) {
error_report("Failed to initialize USB device '%s'", name);
return NULL;
if (!dev) {
error_report("%s", error_get_pretty(err));
error_free(err);
}
return dev;
}
@ -419,7 +440,7 @@ void usb_claim_port(USBDevice *dev, Error **errp)
} else {
if (bus->nfree == 1 && strcmp(object_get_typename(OBJECT(dev)), "usb-hub") != 0) {
/* Create a new hub and chain it on */
usb_create_simple(bus, "usb-hub");
usb_try_create_simple(bus, "usb-hub", NULL);
}
if (bus->nfree == 0) {
error_setg(errp, "tried to attach usb device %s to a bus "