I think the ability to specify a different vendorid + deviceid can be useful. Suppose there is a USB device such that the specifications are open and officially published, but the driver is proprietary. (As far as I know, this is similar to the situation with ATI video cards, but they are not USB devices.) And I suspect that the driver is buggy (i. e. it does not send the data according to the specifications). I want to figure out where exactly it works incorrectly to submit a bug report to the developer of the driver. Or suppose I have a physical device, but it works a bit incorrectly. I want to figure out where exactly the problem is, in the driver or in the device. Since I am not sure that the device is OK, I don't want to write my own driver and interact with the device, maybe I will damage it even more. In both cases, I can emulate the device according to the specifications, install the driver in a guest system, and then see whether the driver sends correct data or where and when exactly the data are incorrect.
Anyway, I think it is more or less ok if qemu crashes right after it starts due to bad command line parameters (nevertherless, the functionality lost this way could be useful as I explained). But I think IT IS NOT OK WHEN A WORKING VM WITH PROGRAMS INSIDE CRASHES after user enters a bad command in the machine's control terminal, unless the user explicitly requests termination (e. g. enters the q command). -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1180924 Title: fails to handle a usb serial port with a specific vendorid Status in QEMU: New Bug description: If I run qemu-system-i386 with arguments -usb -usbdevice serial:vendorid=1221:pty (this is what the documentation says about how I shoud add a usb device which has a serial port interface and which has a specific vendor id, I used the documentation located here: http://qemu.weilnetz.de/qemu-doc.html ), it says char device redirected to /dev/pts/<something> (label usbserial0) qemu-system-i386: -usbdevice serial:vendorid=1221:pty: Property '.vendorid' not found Aborted and exits. Moreover, if I try to add such a device to a running machine by typing usb_add serial:vendorid=1221:pty in the machine's control terminal (to reach it, I press ctrl-alt-2), qemu also writes char device redirected to /dev/pts/<something> (label usbserial0) Aborted to the terminal where I run it from and exits. To the quest OS this looks like a power failure which causes all the programs inside the virtual machine to lose their unsaved data. I have tested this with qemu-1.5.0-rc2, actually, the issue occured in a similar way since 1.0.1, but did not occur in 0.11.1. The issue is reproducible always, even if I don't specify any hard disk in the command line, i. e. $ qemu-system-i386 -usb -usbdevice serial:vendorid=1221:pty , so I believe it is guest OS -independent. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1180924/+subscriptions
