Re: [PATCH] x86/mm: Drop TS_COMPAT on 64-bit exec() syscall

[Dmitry Safonov]

2018-05-19 0:16 GMT+01:00 Dmitry Safonov <0x7f454c46@xxxxxxxxx>:
> 2018-05-19 0:10 GMT+01:00 Dmitry Safonov <0x7f454c46@xxxxxxxxx>:
>> Sure.
>> I'm on Intel actually:
>> cpu family    : 6
>> model        : 142
>> model name    : Intel(R) Core(TM) i7-7600U CPU @ 2.80GHz
>>
>> But I usually test kernels in VM. So, I use virt-manager as it's
>> easier to manage
>> multiple VMs. The thing is that I've chosen "Copy host CPU configuration"
>> and for some reason, I don't quite follow virt-manager makes model "Opteron_G4".
>> I'm on Fedora 27, virt-manager 1.4.3, qemu 2.9.1(qemu-2.9.1-2.fc26).
>
> Hmm, the reason it chooses AMD emulation looks like a bug in virt-manager:
> When I try IvyBridge CPU, it gives the following error:
>> Error starting domain: the CPU is incompatible with host CPU: Host CPU does not
>> provide required features: vme, x2apic, tsc-deadline, avx, f16c, rdrand
>
> Which to my naive mind is by the reason that "tsc-deadline" is not written with
> a dash in cpuinfo:
> flags        : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe
> syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts
> rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq
> pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma
> cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt
> tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch
> cpuid_fault epb invpcid_single pti tpr_shadow vnmi flexpriority ept
> vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx
> rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves
> ibpb ibrs stibp dtherm ida arat pln pts hwp hwp_notify hwp_act_window
> hwp_epp
>
> But that just my naive suppose.

Yeah, so they use cpuid there and I guess this one wasn't fixed for me:
https://bugzilla.redhat.com/show_bug.cgi?id=1467599

Thanks,
             Dmitry