Re: Qemu doesn't detect hard drive

[Markus Armbruster <armbru@redhat.com>]

Philippe Mathieu-Daudé <philmd@redhat.com> writes:

> On 4/3/20 9:39 AM, Peter Maydell wrote:
>> On Fri, 3 Apr 2020 at 06:18, Aijaz.Baig <Aijaz.Baig@protonmail.com> wrote:
>>> I would now like to add a hard disk for persistent storage and then transfer control from busybox initrd based rootfs over to the full fledged version offered with Linux. So I add it to the command line
>>>
>>> `sudo qemu-system-arm -m 1024M -M vexpress-a9 -D qemu.log -drive if=none,format=raw,file=disk.img -kernel buildroot-2019.02.5/output/images/zImage -dtb buildroot-2019.02.5/output/images/vexpress-v2p-ca9.dtb -append "console=ttyAMA0,115200 kgdboc=kbd,ttyAMA0,115200 ip=dhcp nokaslr" -initrd buildroot-2019.02.5/output/images/rootfs.cpio -nographic -net nic -net bridge,br=mybridge -s
>>
>> This command line creates a "drive" object but doesn't plug it in to anything
>> (it's like asking QEMU to model a board, with a hard drive sat next to it
>> on the desk but no cable between them :-))
>
> Should QEMU warn the user about unplugged drives?
>
> Or is it an expected feature (these drives might be hot-plugged later?)

For what it's worth, it warns about unused network backends, but not
about unused block or character backends.  All of them can be connected
later in the monitor.