Re: [Qemu-block] [QEMU + SPDK] The demo in the official document is not working

[Bob Chen]

Problem solved. Got a reply from Intel just now.

---------- Forwarded message ----------
From: Liu, Changpeng <address@hidden>
Date: 2018-04-23 18:06 GMT+08:00
Subject: [Qemu-devel] [QEMU + SPDK] The demo in the official document is not working
To: "address@hidden" <address@hidden>


Hi Bob,

The issues was introduced by the following commit:
commit fb20fbb764 "vhost: avoid to start/stop virtqueue which is not ready". 

When you starting with seabios, the virtio-scsi driver in seabios will only enumerate 1 I/O queue, 
but didn't include task management and event queue,  while SPDK vhost target must get all the 3 queues
when starting, so this process will be blocked at seabios.

One workaround for now, you can start with the chardev, after booting to OS, you can use -device_add to add the
virtio-scsi controller. We are developing the right fix, ethier in seabios or SPDK, this will be fixed very soon.


Best Regards,
Changpeng Liu

2018-04-23 16:19 GMT+08:00 Bob Chen <address@hidden>:

Hi,

I was trying to run qemu with spdk, referring to http://www.spdk.io/doc/vhost.html#vhost_qemu_config . Steps were strictly followed.

# Environment: latest CentOS 7 kernel, nvme ssd, spdk v18.01.x, dpdk 17.11.1, qemu 2.11.1 

 

cd spdk
sudo su
ulimit -l unlimited
HUGEMEM=2048 ./scripts/setup.sh
./app/vhost/vhost -S /var/tmp -s 1024 -m 0x1 &
./scripts/rpc.py construct_nvme_bdev -b Nvme0 -t pcie -a 0000:03:00.0
./scripts/rpc.py construct_malloc_bdev 128 4096 -b Malloc0
./scripts/rpc.py construct_vhost_scsi_controller --cpumask 0x1 vhost.0
./scripts/rpc.py add_vhost_scsi_lun vhost.0 0 Nvme0n1
./scripts/rpc.py add_vhost_scsi_lun vhost.0 1 Malloc0

qemu-system-x86_64 -enable-kvm -cpu host -machine pc,accel=kvm -daemonize -vnc :1 \
-smp 1 -m 1G -object memory-backend-file,id=mem0,size=1G,mem-path=/dev/hugepages,share=on -numa node,memdev=mem0 \
-drive file=<guest-os-image.qcow2>,if=none,id=disk -device ide-hd,drive=disk,bootindex=0 \
-chardev socket,id=spdk_vhost_scsi0,path=/var/tmp/vhost.0 \
-device vhost-user-scsi-pci,id=scsi0,chardev=spdk_vhost_scsi0

Unfortunately the demo was not able to work, stopped at the boot-loader screen saying that not bootable device. But if I removed the last two lines(vhost-user-scsi-pci), the guest could start successfully. So there must be something wrong with the spdk device.

Is there anyone in this community who happened to be familiar with spdk? Or should I seek for help from Intel? Don't know who is responsible for maintaining this document.

 

Thanks,

Bob