Sys-usb (dvm) does not start

After the last update my sys-usb does not start anymore (should auto start with OS). Tried to launch it manually with Qubes Manager, get following error:


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I need one usb device, without that device I am blocked from working.

What is your first guess? Can it be a quick fix?

Should I wait one more day or do you recommend to remove the sys-usb and do a new sys-usb install?

@ludovic @slcoleman I fixed it by simple I changed back the memory settings to 400MB (ini and max). It is still odd to me but currently it is running fine - I have my usb devices listed again and I do not see an error message anymore. @slcoleman could you please test on your side?

Hm fixed memory on sys-usb makes some sense as some devices do not play too well with changing memory sizes IIRC.

That is a fair statement it fixed my issue. I can use my usb devices again.

Since it appeared after the last update and it was not only me facing that issue I expect that some devs do some investigations on this issue.

Thanks for finding that, this actually helped.

I’ve done some testing, and this issue always happens if I set the VMs memory to 2000MB or more.
1900 MB - all fine
2000 MB - broken
2100 MB - broken

I do need additional memory for my webcam to work, but 1900 instead of 2000 should definitely be fine. Still, a strange issue indeed.

Try RAM auto balancing OFF.

In dom0:

qvm-prefs <name of your usb qube> memory 400
qvm-prefs <name of your usb qube> maxmem 0

Yes, balancing has been disabled the entire time.
It might be interesting to see what happens if you set it to 400 - 2500 MB, if it crashes once it reaches 2000. But I’ll leave that for someone else :wink: