> Does qemu follow recommendations from section 4.3? All that QEMU does is initialize MSR values and QEMU is talking to KVM, not to the processor; KVM in turn talks to the host kernel's perf subsystem.
It's the host kernel's perf subsystem that needs to follow Intel's recommendation. In particular, QEMU is setting CPUID to the values retrieved by perf_get_x86_pmu_capability(&cap); so perhaps it's perf_get_x86_pmu_capability that misreads the performance monitoring capabilities provided by ESX. Please attach dmesg logs from starting the host with loglevel=9, as well as "x86info -a" output from the host, to see if perf misses some problematic CPUID/MSR combination. -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1661386 Title: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed Status in QEMU: New Bug description: Hello, I see the following when try to run qemu from master as the following: # ./x86_64-softmmu/qemu-system-x86_64 --version QEMU emulator version 2.8.50 (v2.8.0-1006-g4e9f524) Copyright (c) 2003-2016 Fabrice Bellard and the QEMU Project developers # ./x86_64-softmmu/qemu-system-x86_64 -machine accel=kvm -nodefaults -no-reboot -nographic -cpu host -vga none -kernel .build.kernel.kvm -initrd .build.initrd.kvm -append 'panic=1 no-kvmclock console=ttyS0 loglevel=7' -m 1024 -serial stdio qemu-system-x86_64: /home/matwey/lab/qemu/target/i386/kvm.c:1849: kvm_put_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed. First broken commit has been bisected: commit 48e1a45c3166d659f781171a47dabf4a187ed7a5 Author: Paolo Bonzini <pbonz...@redhat.com> Date: Wed Mar 30 22:55:29 2016 +0200 target-i386: assert that KVM_GET/SET_MSRS can set all requested MSRs This would have caught the bug in the previous patch. Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> My cpuinfo is the following: processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 44 model name : Intel(R) Xeon(R) CPU X5675 @ 3.07GHz stepping : 2 microcode : 0x14 cpu MHz : 3066.775 cache size : 12288 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 11 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc aperfmperf pni pclmulqdq vmx ssse3 cx16 sse4_1 sse4_2 popcnt aes hypervisor lahf_lm ida arat epb dtherm tpr_shadow vnmi ept vpid bugs : bogomips : 6133.55 clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1661386/+subscriptions