Re: [Qemu-devel] NVDIMM live migration broken?

[haozhong.zhang]

On 06/22/17 15:08 +0100, Stefan Hajnoczi wrote:
> I tried live migrating a guest with NVDIMM on qemu.git/master (edf8bc984):
> 
>   $ qemu -M accel=kvm,nvdimm=on -m 1G,slots=4,maxmem=8G -cpu host \
>          -object 
> memory-backend-file,id=mem1,share=on,mem-path=nvdimm.dat,size=1G \
>        -device nvdimm,id=nvdimm1,memdev=mem1 \
>        -drive if=virtio,file=test.img,format=raw
> 
>   $ qemu -M accel=kvm,nvdimm=on -m 1G,slots=4,maxmem=8G -cpu host \
>          -object 
> memory-backend-file,id=mem1,share=on,mem-path=nvdimm.dat,size=1G \
>        -device nvdimm,id=nvdimm1,memdev=mem1 \
>        -drive if=virtio,file=test.img,format=raw \
>        -incoming tcp::1234
> 
>   (qemu) migrate tcp:127.0.0.1:1234
> 
> The guest kernel panics or hangs every time on the destination.  It
> happens as long as the nvdimm device is present - I didn't even mount it
> inside the guest.
> 
> Is migration expected to work?

Yes, I tested on QEMU 2.8.0 several months ago and it worked. I'll
have a look at this issue.

Haozhong

> 
> If not we need a migration blocker so that users get a graceful error
> message.
> 
> Stefan