Public bug reported: == Comment: #0 - SEETEENA THOUFEEK <[email protected]> - 2024-06-25 01:24:11 == +++ This bug was initially created as a clone of Bug #205277 +++
---Problem Description--- KOP L2 guest fails to boot with 1 core - SMT8 topology ---Additional Hardware Info--- na ---Debugger Data--- na ---Steps to Reproduce--- KOP L2 guest fails to boot when we set the CPU topology as 1 core - SMT 8 command line used to verify the issue: #!/bin/sh QEMU="/home/mgautam/qemu" qemu-system-ppc64 -s \ -drive file=/root/debian-12-nocloud-ppc64el.qcow2,format=qcow2 \ -m 20G \ -smp 8,cores=1,sockets=1,threads=8 \ -cpu host \ -nographic \ -machine pseries,ic-mode=xics -accel kvm \ -net nic,model=virtio \ -net user,host=10.0.2.10,hostfwd=tcp:127.0.0.1:10022-:22 NOTE: L2 boots fine when doorbells are turned off in L1 kernel As per the investigation so far, the doorbell exception is not getting fired inside L2 guest. At L1 level, if we set DPDES=1 in the GSB for L2, the guest never receives the doorbell and also it is never cleared from the GSB. We are discussing this behaviour with phyp team. The root cause of this issue is lack of DPDES support at L1. I've posted the fix upstream - https://lore.kernel.org/linuxppc- dev/[email protected]/T/#u The fix has been accepted upstream and will be backported for kernels >= 6.7 https://lore.kernel.org/linuxppc-dev/[email protected]/ ---Patches Installed--- na ---System Hang--- na ---uname output--- na Contact Information = na Machine Type = na Userspace rpm: na Userspace tool common name: na The userspace tool has the following bit modes: na Userspace tool obtained from project website: na *Additional Instructions for na: -Post a private note with access information to the machine that is currently in the debugger. -Attach ltrace and strace of userspace application. ** Affects: linux (Ubuntu) Importance: Undecided Assignee: Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) Status: New ** Tags: architecture-ppc64 bugnameltc-207101 severity-high targetmilestone-inin--- ** Tags added: architecture-ppc64 bugnameltc-207101 severity-high targetmilestone-inin--- ** Changed in: ubuntu Assignee: (unassigned) => Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) ** Package changed: ubuntu => linux (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2070329 Title: KOP L2 guest fails to boot with 1 core - SMT8 topology (Fedora) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2070329/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
