other: 0.621 graphic: 0.591 permissions: 0.523 device: 0.454 semantic: 0.443 PID: 0.442 KVM: 0.441 debug: 0.398 performance: 0.396 vnc: 0.393 socket: 0.387 files: 0.376 boot: 0.361 network: 0.344 qemu does not generate guest cpu topology properly Adding the option -smp 12,sockets=2,cores=6,threads=1 exposes Machine (12GB) Socket #0 L2 L#0 (512KB) + L1 L#0 (64KB) + Core L#0 + PU L#0 (P#0) L2 L#1 (512KB) + L1 L#1 (64KB) + Core L#1 + PU L#1 (P#1) L2 L#2 (512KB) + L1 L#2 (64KB) + Core L#2 + PU L#2 (P#2) L2 L#3 (512KB) + L1 L#3 (64KB) + Core L#3 + PU L#3 (P#3) L2 L#4 (512KB) + L1 L#4 (64KB) + Core L#4 + PU L#4 (P#4) L2 L#5 (512KB) + L1 L#5 (64KB) + Core L#5 + PU L#5 (P#5) L2 L#6 (512KB) + L1 L#6 (64KB) + Core L#6 + PU L#6 (P#6) L2 L#7 (512KB) + L1 L#7 (64KB) + Core L#7 + PU L#7 (P#7) Socket #1 L2 L#8 (512KB) + L1 L#8 (64KB) + Core L#8 + PU L#8 (P#8) L2 L#9 (512KB) + L1 L#9 (64KB) + Core L#9 + PU L#9 (P#9) L2 L#10 (512KB) + L1 L#10 (64KB) + Core L#10 + PU L#10 (P#10) L2 L#11 (512KB) + L1 L#11 (64KB) + Core L#11 + PU L#11 (P#11) Rather than: Machine (12GB) Socket #0 L2 L#0 (512KB) + L1 L#0 (64KB) + Core L#0 + PU L#0 (P#0) L2 L#1 (512KB) + L1 L#1 (64KB) + Core L#1 + PU L#1 (P#1) L2 L#2 (512KB) + L1 L#2 (64KB) + Core L#2 + PU L#2 (P#2) L2 L#3 (512KB) + L1 L#3 (64KB) + Core L#3 + PU L#3 (P#3) L2 L#4 (512KB) + L1 L#4 (64KB) + Core L#4 + PU L#4 (P#4) L2 L#5 (512KB) + L1 L#5 (64KB) + Core L#5 + PU L#5 (P#5) Socket #1 L2 L#6 (512KB) + L1 L#6 (64KB) + Core L#6 + PU L#6 (P#6) L2 L#7 (512KB) + L1 L#7 (64KB) + Core L#7 + PU L#7 (P#7) L2 L#8 (512KB) + L1 L#8 (64KB) + Core L#8 + PU L#8 (P#8) L2 L#9 (512KB) + L1 L#9 (64KB) + Core L#9 + PU L#9 (P#9) L2 L#10 (512KB) + L1 L#10 (64KB) + Core L#10 + PU L#10 (P#10) L2 L#11 (512KB) + L1 L#11 (64KB) + Core L#11 + PU L#11 (P#11) Here is a cpuid dump from inside the guest and dump from more recent version of cpuid, in which you can see a bit more detail. The later contains data for a single CPU, because the others are the same. Reproducible on qemu 1.0 and 1.2. with guest os Fedora 17, Debian 6, Debian Squeeze and Windows 2008 R2. Triaging old bug tickets... can you still reproduce this issue with the latest version of QEMU? Or could we close this ticket nowadays? [Expired for QEMU because there has been no activity for 60 days.]