[Bug 1943729] Re: AMD impish Libvirt7.6 nested amd-v, rbd storage broken

[Launchpad Bug Tracker]

[Expired for linux (Ubuntu) because there has been no activity for 60
days.]

** Changed in: linux (Ubuntu)
       Status: Incomplete => Expired

-- 
You received this bug notification because you are a member of Ubuntu
OpenStack, which is subscribed to ceph in Ubuntu.
https://bugs.launchpad.net/bugs/1943729

Title:
  AMD impish Libvirt7.6 nested amd-v, rbd storage broken

Status in ceph package in Ubuntu:
  Expired
Status in libvirt package in Ubuntu:
  Expired
Status in linux package in Ubuntu:
  Expired
Status in qemu package in Ubuntu:
  Expired

Bug description:
  Hello,

  Having issues with AMD and RBD Driver. Running on latest impish, using
  libvirt7.6ubuntu1.

  Having following setup (not sure if matters):

  Dedicated-Host (AMD) -> Level1-KVM (cpu-pass-through, rbd) ->
  "Customer-VM"=CVM

  ubuntu20.04 -> impish -> custom

  What happens?

  It seems Level1-KVM is struggeling with RBD storage access,
  breaking/preventing CVM's operating system to fully boot. Half of the
  booting process is going through, but later at random point in time
  (still booting the kernel) it seems to deadlock, letting CVM's CPU
  spin endless.

  Following tests setups i verified to isolate the issue:

  Dedicated-Host (Intel) -> Level1-KVM (impish=7.6,cpu-pass-through,
  rbd=virtio) -> CVM = works

  Dedicated-Host (AMD) -> Level1-KVM (impish=7.6,cpu-pass-through,
  direct storage=virtio) -> CVM = works

  
  Dedicated-Host (Intel) -> Level1-KVM (focal=6.0,cpu-pass-through, rbd=virtio) -> CVM = works

  Dedicated-Host (AMD) -> Level1-KVM (focal=6.0,cpu-pass-through,
  rbd=virtio) -> CVM = works

  Dedicated-Host (AMD) -> Level1-KVM (focal=6.0,cpu-pass-through, direct
  storage=virtio) -> CVM = works

  
  -----------------------------------------------

  Dedicated-Host (AMD) -> Level1-KVM (impish=7.6,cpu-pass-through,
  rbd=virtio) -> CVM = stuck

  Out of those tests, the issue seems to be IMO located in libvirt 7.6,
  sadly im not able to check it against 7.4 (which was shortly available
  for impish, but was already removed from the repo mirror..).

  Any idears what could make an AMD passthrough break access of RBD,
  letting CVM stuck accessing storage?

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/ceph/+bug/1943729/+subscriptions