Re: [Qemu-discuss] qemu-system-arm -M virt v3.0.0-rc4 Linux kernel virtio boots fails with VFS: Cannot open root device "vda"

[Nerijus Baliunas]

On Thu, 9 Aug 2018 22:59:27 +0100 Ciro Santilli <address@hidden> wrote:

> Analogous commands work for x86_64 and aarch64
> 
> All worked on v2.12.0 with the same images.

> Kernel boot error message:
> VFS: Cannot open root device "vda" or unknown-block(0,0): error -6

I have just tried to boot my armv7l virt-3.0 VM, which has root on /dev/vda3, 
and it boots
successfully with 3.0.0-rc4. One is configured as Direct kernel boot and has
Kernel args: console=ttyAMA0 rw root=UUID=00d450fb-138b-4faa-b2d2-c6c79950fb56  
rootwait
(IIRC I had to add root=UUID= option about 2 years ago, it booted w/o it 
before),
and another is UEFI. I use libvirt, command lines for both are:

/usr/bin/qemu-system-arm -name guest=fedora28-arm,debug-threads=on -S -object 
secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-7-fedora28-arm/master-key.aes
 -machine virt-3.0,accel=tcg,usb=off,dump-guest-core=off -m 2048 -realtime 
mlock=off -smp 1,sockets=1,cores=1,threads=1 -uuid 
1afe58e9-f943-4ffe-889c-a3a6a4687937 -display none -no-user-config -nodefaults 
-chardev 
socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-7-fedora28-arm/monitor.sock,server,nowait
 -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown 
-boot strict=on -kernel 
/var/lib/libvirt/images/vmlinuz-4.17.12-200.fc28.armv7hl -initrd 
/var/lib/libvirt/images/initramfs-4.17.12-200.fc28.armv7hl.img -append 
console=ttyAMA0 rw root=UUID=00d450fb-138b-4faa-b2d2-c6c79950fb56  rootwait 
-device i82801b11-bridge,id=pci.1,bus=pcie.0,addr=0x1 -device 
pci-bridge,chassis_nr=2,id=pci.2,bus=pci.1,addr=0x1 -drive 
file=/var/lib/libvirt/images/Fedora-Server-armhfp-22-TC4-sda.qcow2,format=qcow2,if=none,id=drive-virtio-disk0
 -device 
virtio-blk-device,scsi=off,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 
-netdev tap,fd=26,id=hostnet0 -device 
virtio-net-device,netdev=hostnet0,id=net0,mac=52:54:00:f1:3b:de -chardev 
pty,id=charserial0 -serial chardev:charserial0 -msg timestamp=on

/usr/bin/qemu-system-arm -name guest=fedora28-arm-uefi,debug-threads=on -S 
-object 
secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-8-fedora28-arm-uefi/master-key.aes
 -machine virt-3.0,accel=tcg,usb=off,dump-guest-core=off -cpu cortex-a15 -drive 
file=/usr/share/edk2.git/arm/QEMU_EFI-pflash.raw,if=pflash,format=raw,unit=0,readonly=on
 -drive 
file=/var/lib/libvirt/qemu/nvram/fedora28-arm-uefi_VARS.fd,if=pflash,format=raw,unit=1
 -m 2048 -realtime mlock=off -smp 1,sockets=1,cores=1,threads=1 -uuid 
1b721aaa-0d2b-48f8-9697-ccca9f361248 -display none -no-user-config -nodefaults 
-chardev 
socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-8-fedora28-arm-uefi/monitor.sock,server,nowait
 -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown 
-boot strict=on -device virtio-serial-device,id=virtio-serial0 -drive 
file=/var/lib/libvirt/images/Fedora-Server-armhfp-22-TC4-sda.qcow2,format=qcow2,if=none,id=drive-virtio-disk0
 -device 
virtio-blk-device,scsi=off,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 
-netdev tap,fd=26,id=hostnet0 -device 
virtio-net-device,netdev=hostnet0,id=net0,mac=52:54:00:f1:3b:de -chardev 
pty,id=charserial0 -serial chardev:charserial0 -chardev 
socket,id=charchannel0,path=/var/lib/libvirt/qemu/channel/target/domain-8-fedora28-arm-uefi/org.qemu.guest_agent.0,server,nowait
 -device 
virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0
 -msg timestamp=on

Regards,
Nerijus