text-tsx fails on Intel core 8th gen system

[Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>]

Hi,

I've noticed that tools/tests/tsx/test-tsx fails on a system with Intel
Core i7-8750H. Specific error I get:

    [user@dom0 tsx]$ ./test-tsx 
    TSX tests
      Got 16 CPUs
    Testing MSR_TSX_FORCE_ABORT consistency
      CPU0 val 0
    Testing MSR_TSX_CTRL consistency
    Testing MSR_MCU_OPT_CTRL consistency
      CPU0 val 0
    Testing RTM behaviour
      Got #UD
      Host reports RTM, but appears unavailable
    Testing PV default/max policies
      Max: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
      Def: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
      HLE/RTM offered to guests despite not being available
    Testing HVM default/max policies
      Max: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
      Def: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
      HLE/RTM offered to guests despite not being available
    Testing PV guest
      Created d8
      Cur: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
      Cur: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
    Testing HVM guest
      Created d9
      Cur: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
      Cur: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
    [user@dom0 tsx]$ echo $?
    1


When I try it on a newer system (11th gen) then it works fine (exit code
0, just "Got #UD", no "Host reports RTM, but appears unavailable" line).


/proc/cpuinfo says:

    processor   : 0
    vendor_id   : GenuineIntel
    cpu family  : 6
    model               : 158
    model name  : Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz
    stepping    : 10
    microcode   : 0xf6
    cpu MHz             : 2207.990
    cache size  : 9216 KB
    physical id : 0
    siblings    : 6
    core id             : 0
    cpu cores   : 1
    apicid              : 0
    initial apicid      : 0
    fpu         : yes
    fpu_exception       : yes
    cpuid level : 13
    wp          : yes
    flags               : fpu de tsc msr pae mce cx8 apic sep mca cmov pat 
clflush acpi mmx fxsr sse sse2 ss ht syscall nx rdtscp lm constant_tsc rep_good 
nopl nonstop_tsc cpuid tsc_known_freq pni pclmulqdq monitor est ssse3 fma cx16 
sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm abm 
3dnowprefetch cpuid_fault ssbd ibrs ibpb stibp fsgsbase bmi1 avx2 bmi2 erms 
rdseed adx clflushopt xsaveopt xsavec xgetbv1 md_clear arch_capabilities
    bugs                : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass 
l1tf mds swapgs itlb_multihit srbds mmio_stale_data retbleed
    bogomips    : 4415.98
    clflush size        : 64
    cache_alignment     : 64
    address sizes       : 39 bits physical, 48 bits virtual
    power management:

    ...


Full `xen-cpuid detail` output attached.

Just in case, I'm attaching also full xl dmesg, but I don't see anything
related there.

-- 
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab

Attachment: xen-cpuid.txt
Description: Text document

Attachment: xl-dmesg.txt
Description: Text document

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