Re: [virtio-dev] [PATCH v3 00/15] virtio-mem: paravirtualized memory

David Hildenbrand
2020-05-14T11:11:20Z

On 14.05.20 12:12, David Hildenbrand wrote:
> On 14.05.20 12:02, teawater wrote:
>>
>>
>>> 2020年5月14日 16:48，David Hildenbrand <david@redhat.com> 写道：
>>>
>>> On 14.05.20 08:44, teawater wrote:
>>>> Hi David,
>>>>
>>>> I got a kernel warning with v2 and v3.
>>>
>>> Hi Hui,
>>>
>>> thanks for playing with the latest versions. Surprisingly, I can
>>> reproduce even by hotplugging a DIMM instead as well - that's good, so
>>> it's not related to virtio-mem, lol. Seems to be some QEMU setup issue
>>> with older machine types.
>>>
>>> Can you switch to a newer qemu machine version, especially
>>> pc-i440fx-5.0? Both, hotplugging DIMMs and virtio-mem works for me with
>>> that QEMU machine just fine.
>>
>> I still could reproduce this issue with pc-i440fx-5.0 or pc. Did I miss anything?
>>
>
> Below I don't even see virtio_mem. I had to repair the image (filesystem
> fsck) because it was broken, can you try that as well?
>
> Also, it would be great if you could test with v4.
>

Correction, something seems to be broken either in QEMU or the kernel. Once I
define a DIMM so it's added and online during boot, I get these issues:

(I have virtio-mem v4 installed in the guest)

#! /bin/bash
sudo x86_64-softmmu/qemu-system-x86_64 \
-machine pc-i440fx-5.0,accel=kvm,usb=off \
-cpu host \
-no-reboot \
-nographic \
-device ide-hd,drive=hd \
-drive if=none,id=hd,file=/home/dhildenb/git/Fedora-Cloud-Base-31-1.9.x86_64.qcow2,format=qcow2 \
-m 1g,slots=10,maxmem=2G \
-smp 1 \
-object memory-backend-ram,id=mem0,size=256m \
-device pc-dimm,id=dimm0,memdev=mem0 \
-s \
-monitor unix:/var/tmp/monitor,server,nowait

Without the DIMM it seems to work just fine.

--
Thanks,

David / dhildenb