I gave that reproducer a try and it failed after 1968 iterations. * CPU: Intel(R) Core(TM) i9-9900KS * qemu: qemu-kvm-7.2.1-2.fc38.x86_64 * host kernel: 6.3.

I gave that reproducer a try and it failed after 1968 iterations. * CPU: Intel(R) Core(TM) i9-9900KS * qemu: qemu-kvm-7.2.1-2.fc38.x86_64 * host kernel: 6.3.6-200.fc38.x86_64 * guest kernel: 6.4.0-0.rc6.48.fc39.x86_64 (grabbed latest from mirrors.kernel.org/fedora since fedoraproject.org DNS is down and I can't access koji) Log: <...> 1966... 1967... 1968... [ 0.075343] LSM: initializing lsm=lockdown,capability,yama,bpf,landlock,integrity [ 0.075514] Yama: becoming mindful. [ 0.075514] LSM support for eBPF active [ 0.075514] landlock: Up and running. [ 0.075514] Mount-cache hash table entries: 4096 (order: 3, 32768 bytes, linear) [ 0.075514] Mountpoint-cache hash table entries: 4096 (order: 3, 32768 bytes, linear) [ 0.075514] x86/cpu: User Mode Instruction Prevention (UMIP) activated [ 0.075514] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0 [ 0.075514] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0 [ 0.075514] Spectre V1 : Mitigation: usercopy/swapgs barriers and __user pointer sanitization [ 0.075514] Spectre V2 : Mitigation: Enhanced / Automatic IBRS [ 0.075514] Spectre V2 : Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch [ 0.075514] Spectre V2 : Spectre v2 / PBRSB-eIBRS: Retire a single CALL on VMEXIT [ 0.075514] RETBleed: Mitigation: Enhanced IBRS [ 0.075514] Spectre V2 : mitigation: Enabling conditional Indirect Branch Prediction Barrier [ 0.075514] Speculative Store Bypass: Mitigation: Speculative Store Bypass disabled via prctl [ 0.075514] TAA: Mitigation: TSX disabled [ 0.075514] MMIO Stale Data: Vulnerable: Clear CPU buffers attempted, no microcode [ 0.075514] SRBDS: Unknown: Dependent on hypervisor status [ 0.075514] Freeing SMP alternatives memory: 48K *** ERROR OR HANG *** I'll try reverting f31dcb152a3 and testing again later. Happy to test anything else if needed.