Re: Qemu doesn't detect hard drive

[Peter Maydell]

On Fri, 3 Apr 2020 at 06:18, Aijaz.Baig <address@hidden> 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 :-))

More generally, the vexpress-a9 board does not support hard disks.
This is because the real hardware we're modelling here has no disk
drive interfaces and no PCI or similar bus that you could plug a
scsi controller into. The best it can do for storage is an SD card
emulation, which works but the performance is not great.

thanks
-- PMM