Re: Error : init: partition(s) not found in /sys, waiting for their uevent(s): mmcblk0p2, mmcblk0p3 while trying to emulate Android 14 on Ubuntu 24.04 X64 bit using qemu-system-aarch64.

[Pierrick Bouvier]

Hello Mario,

very recently, I had to investigate booting time of Android when using 
QEMU. You can probably manage to boot this with only QEMU alone, but in 
my experience, using Cuttlefish tooling is an easier approach.

If you really want to use only QEMU, you can use Cuttlefish to get exact 
command line used (which disk goes where), and iterate from that.

Instructions: 
https://linaro.atlassian.net/wiki/spaces/QEMU/pages/29464068097/Run+Android+using+QEMU

As you'll see, I could not get a direct graphic output, but using 
scrcpy, it worked well for me. Hope it can fit your use case.

Regards,
Pierrick

On 9/2/24 06:49, Mario Marietto wrote:
> Hello.
>
> I would like to emulate Android 14 on my Ubuntu 24.04 OS X64 bit using 
> qemu-system-aarch64. I tried using the following parameters :
>
> qemu-system-aarch64 \
>          -smp 4 \
>          -m 2048 \
>          -cpu cortex-a72 \
>          -M virt \
>          -device virtio-gpu-pci,xres=1024,yres=768 \
>          -display sdl,gl=on \
>          -device usb-ehci \
>          -device usb-kbd \
>          -device virtio-tablet-pci \
>          -usb \
>          -serial stdio \
>          -kernel /mnt/zroot-133/_OS/Android/rpi4/Image \
>          -initrd /mnt/zroot-133/_OS/Android/rpi4/ramdisk.img \
>          -drive 
> index=0,if=none,id=system,file=/mnt/zroot-133/_OS/Android/rpi4/boot.img \
>          -device virtio-blk-pci,drive=boot \
>          -drive 
> index=1,if=none,id=system,file=/mnt/zroot-133/_OS/Android/rpi4/system.img \
>          -device virtio-blk-pci,drive=system \
>          -drive 
> index=2,if=none,id=vendor,file=/mnt/zroot-133/_OS/Android/rpi4/vendor.img \
>          -device virtio-blk-pci,drive=vendor \
> -append "console=ttyAMA0,38400 drm.debug=0x0 rootwait rootdelay=5 
> root=/dev/mmcblk0p2 androidboot.hardware=rpi4 
> androidboot.selinux=permissive security=selinux selinux=1 
> androidboot.qemu.hw.mainkeys=0 androidboot.lcd.density=160"
>
> The error I get in short is :
>
> [ 1.993668] init: bool 
> android::init::BlockDevInitializer::InitDevices(std::set<std::string>): 
> partition(s) not found in /sys, waiting for their uevent(s): mmcblk0p2, 
> mmcblk0p3
>
>
> One user suggested to :
>
>
>
>
>         
> Hi!!! The "/sys" is a "dynamic fs" created at ram from the kernel, to 
> export a lot of things...so most of the files only exist at runtime. 
> Normally, the partitions from the block device have a symlink at 
> /sys/<something>/<...> that points to /dev/ block node. It seems that 
> there are no such files under /sys according to what init is looking 
> for. You can double check this at init source code to check the exact 
> path but I'm guessing that you'll have to change the qemu arguments 
> regarding the block device.
>
> About userdata.img I think it's normal since in the old days, the image 
> was a "empty sparse image", that means, at the first flashing process, 
> there isn't userdata information, we're just "flashing the partition" 
> with empty data.
> Tks!!!
>
>
>         
> So,in short I should change the qemu arguments regarding the block 
> device. I tried in this way :
>
>
> qemu-system-aarch64 \
>          -smp 4 \
>          -m 2048 \
>          -cpu cortex-a72 \
>          -M virt \
>          -device virtio-gpu-pci,xres=1024,yres=768 \
>          -display sdl,gl=on \
>          -device usb-ehci \
>          -device usb-kbd \
>          -device virtio-tablet-pci \
>          -usb \
>          -serial stdio \
>          -kernel /mnt/zroot-133/_OS/Android/rpi4/Image \
>          -initrd /mnt/zroot-133/_OS/Android/rpi4/ramdisk.img \
>          -hda /mnt/zroot-133/_OS/Android/rpi4/boot.img \
>          -hdb /mnt/zroot-133/_OS/Android/rpi4/system.img \
>          -hdc /mnt/zroot-133/_OS/Android/rpi4/vendor.img \
>        -append "console=ttyAMA0,38400 drm.debug=0x0 rootwait rootdelay=5 
> root=/dev/mmcblk0p2 androidboot.hardware=rpi4 
> androidboot.selinux=permissive security=selinux selinux=1 
> androidboot.qemu.hw.mainkeys=0 androidboot.lcd.density=160"
>
>
> but the error is still there. Do you know some different alternative 
> block devices to try ? thanks.
>
>
> --
> Mario.