<div dir="ltr">I am using a debian 9 guest, hosted on a ESXi platform with nested virtualisation enabled. <div> </div><div>On this debian 9 guest when I run libguesfs-test-tool, it fails with an error: "qemu-system-x86_64: /build/qemu-DqynNa/qemu-2.8+dfsg/target-i386/kvm.c:1805: kvm_put_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed."Instead when I use a wrapper script and hook it with the env variable LIBGUESTFS_HV=/tmp/qemu.wrapper, things work fine, as in the script I just spawn the guest with the specific machine type pc-i440fx-2.1 over KVM.exec qemu-system-x86_64 -enable-kvm -machine pc-i440fx-2.1,accel=kvm,dump-guest-core=off "${args[@]}" The script is attached as well as the libguestfs-test-tool logs. Can anybody help me on this. Why is the latest machine type, i.e. pc-i440fx-2.8 on my debian 9 guest not working out? If I do a force_tcg it works even with the latest machine type, but that is not what I desire, I don't intend libguestfs to run on emulation. ========================================================================================================================= System configuration:$> uname -a Linux XXXX 4.9.0-6-amd64 #1 SMP Debian 4.9.82-1+deb9u3 (2018-03-02) x86_64 GNU/Linux $> kvm -machine help Supported machines are: pc Standard PC (i440FX + PIIX, 1996) (alias of pc-i440fx-2.8) pc-i440fx-2.8 Standard PC (i440FX + PIIX, 1996) (default) pc-i440fx-2.7 Standard PC (i440FX + PIIX, 1996) pc-i440fx-2.6 Standard PC (i440FX + PIIX, 1996) pc-i440fx-2.5 Standard PC (i440FX + PIIX, 1996) pc-i440fx-2.4 Standard PC (i440FX + PIIX, 1996) pc-i440fx-2.3 Standard PC (i440FX + PIIX, 1996) pc-i440fx-2.2 Standard PC (i440FX + PIIX, 1996) pc-i440fx-2.1 Standard PC (i440FX + PIIX, 1996) pc-i440fx-2.0 Standard PC (i440FX + PIIX, 1996) pc-i440fx-1.7 Standard PC (i440FX + PIIX, 1996) pc-i440fx-1.6 Standard PC (i440FX + PIIX, 1996) pc-i440fx-1.5 Standard PC (i440FX + PIIX, 1996) pc-i440fx-1.4 Standard PC (i440FX + PIIX, 1996) pc-1.3 Standard PC (i440FX + PIIX, 1996) pc-1.2 Standard PC (i440FX + PIIX, 1996) pc-1.1 Standard PC (i440FX + PIIX, 1996) pc-1.0 Standard PC (i440FX + PIIX, 1996) pc-0.15 Standard PC (i440FX + PIIX, 1996) pc-0.14 Standard PC (i440FX + PIIX, 1996) pc-0.13 Standard PC (i440FX + PIIX, 1996) pc-0.12 Standard PC (i440FX + PIIX, 1996) pc-0.11 Standard PC (i440FX + PIIX, 1996) pc-0.10 Standard PC (i440FX + PIIX, 1996) q35 Standard PC (Q35 + ICH9, 2009) (alias of pc-q35-2.8) pc-q35-2.8 Standard PC (Q35 + ICH9, 2009) pc-q35-2.7 Standard PC (Q35 + ICH9, 2009) pc-q35-2.6 Standard PC (Q35 + ICH9, 2009) pc-q35-2.5 Standard PC (Q35 + ICH9, 2009) pc-q35-2.4 Standard PC (Q35 + ICH9, 2009) isapc ISA-only PC none empty machine xenfv Xen Fully-virtualized PC xenpv Xen Para-virtualized PC $> kvm -cpu helpAvailable CPUs:x86 486x86 Broadwell-noTSX Intel Core Processor (Broadwell, no TSX)x86 Broadwell Intel Core Processor (Broadwell)x86 Conroe Intel Celeron_4x0 (Conroe/Merom Class Core 2)x86 Haswell-noTSX Intel Core Processor (Haswell, no TSX)x86 Haswell Intel Core Processor (Haswell)x86 IvyBridge Intel Xeon E3-12xx v2 (Ivy Bridge)x86 Nehalem Intel Core i7 9xx (Nehalem Class Core i7)x86 Opteron_G1 AMD Opteron 240 (Gen 1 Class Opteron)x86 Opteron_G2 AMD Opteron 22xx (Gen 2 Class Opteron)x86 Opteron_G3 AMD Opteron 23xx (Gen 3 Class Opteron)x86 Opteron_G4 AMD Opteron 62xx class CPUx86 Opteron_G5 AMD Opteron 63xx class CPUx86 Penryn Intel Core 2 Duo P9xxx (Penryn Class Core 2)x86 SandyBridge Intel Xeon E312xx (Sandy Bridge)x86 Skylake-Client Intel Core Processor (Skylake)x86 Westmere Westmere E56xx/L56xx/X56xx (Nehalem-C)x86 athlon QEMU Virtual CPU version 2.5+x86 core2duo Intel(R) Core(TM)2 Duo CPU T7700 @ 2.40GHzx86 coreduo Genuine Intel(R) CPU T2600 @ 2.16GHzx86 kvm32 Common 32-bit KVM processorx86 kvm64 Common KVM processorx86 n270 Intel(R) Atom(TM) CPU N270 @ 1.60GHzx86 pentiumx86 pentium2x86 pentium3x86 phenom AMD Phenom(tm) 9550 Quad-Core Processorx86 qemu32 QEMU Virtual CPU version 2.5+x86 qemu64 QEMU Virtual CPU version 2.5+x86 host KVM processor with all supported host features (only available in KVM mode) Recognized CPUID flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 pn clflush ds acpi mmx fxsr sse sse2 ss ht tm ia64 pbe pni pclmulqdq dtes64 monitor ds-cpl vmx smx est tm2 ssse3 cid fma cx16 xtpr pdcm pcid dca sse4.1 sse4.2 x2apic movbe popcnt tsc-deadline aes xsave osxsave avx f16c rdrand hypervisor fsgsbase tsc-adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx avx512f avx512dq rdseed adx smap avx512ifma pcommit clflushopt clwb avx512pf avx512er avx512cd avx512bw avx512vl avx512vbmi umip pku ospke rdpid avx512-4vnniw avx512-4fmaps syscall nx mmxext fxsr-opt pdpe1gb rdtscp lm 3dnowext 3dnow lahf-lm cmp-legacy svm extapic cr8legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt lwp fma4 tce nodeid-msr tbm topoext perfctr-core perfctr-nb invtsc xstore xstore-en xcrypt xcrypt-en ace2 ace2-en phe phe-en pmm pmm-en kvmclock kvm-nopiodelay kvm-mmu kvmclock kvm-asyncpf kvm-steal-time kvm-pv-eoi kvm-pv-unhalt kvmclock-stable-bit npt lbrv svm-lock nrip-save tsc-scale vmcb-clean flushbyasid decodeassists pause-filter pfthreshold xsaveopt xsavec xgetbv1 xsaves arat </div></div>