Re: Is 2nd Generation Intel(R) Xeon(R) Processors (Formerly Cascade Lake) affected by MDS

[Greg Kroah-Hartman]

On Fri, May 24, 2019 at 03:19:34PM +0200, Jinpu Wang wrote:
> Resend with plain text, and remove confidential unnecessary signature.
> sorry for spam.
> 
> Hi Thomas, hi Greg, hi Tony, hi Arjan, hi other expert on the list
> 
> I noticed on our Cascade lake with 4.14.120,  the kernel is reporting
> vulnerable:
> jwang@ps401a-912:~$ head /sys/devices/system/cpu/vulnerabilities/mds
> Vulnerable: Clear CPU buffers attempted, no microcode; SMT vulnerable
> 
> But according to INTEL,  they have built the mitigation in hardware
> for Cascade Lake:
> https://www.intel.com/content/www/us/en/architecture-and-technology/engineering-new-protections-into-hardware.html
> 
> We are using latest microcode from debian:
> https://metadata.ftp-master.debian.org/changelogs//non-free/i/intel-microcode/intel-microcode_3.20190514.1~deb9u1_changelog
> lscpu:
> jwang@ps401a-912:~$ lscpu
> Architecture:          x86_64
> CPU op-mode(s):        32-bit, 64-bit
> Byte Order:            Little Endian
> CPU(s):                96
> On-line CPU(s) list:   0-95
> Thread(s) per core:    2
> Core(s) per socket:    24
> Socket(s):             2
> NUMA node(s):          2
> Vendor ID:             GenuineIntel
> CPU family:            6
> Model:                 85
> Model name:            Intel(R) Xeon(R) Platinum 8268 CPU @ 2.90GHz
> Stepping:              5
> CPU MHz:               3228.226
> CPU max MHz:           3900.0000
> CPU min MHz:           1000.0000
> BogoMIPS:              5800.00
> Virtualization:        VT-x
> L1d cache:             32K
> L1i cache:             32K
> L2 cache:              1024K
> L3 cache:              33792K
> NUMA node0 CPU(s):     0-23,48-71
> NUMA node1 CPU(s):     24-47,72-95
> 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 pni pclmulqdq
> dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm
> pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes
> xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3
> cdp_l3 invpcid_single intel_ppin ssbd mba ibrs ibpb stibp tpr_shadow
> vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2
> erms invpcid rtm cqm mpx rdt_a avx512f avx512dq rdseed adx smap
> clflushopt clwb intel_pt avx512cd avx512bw avx512vl xsaveopt xsavec
> xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local
> dtherm ida arat pln pts pku ospke flush_l1d arch_capabilities
> 
> Clearly we want to buy Cascade Lake if the hardware mitigations are in
> place, but the information on the internet is quite limited and
> misleading.
> 
> Could anyone of you could clarify it for us?
> Does it mean 4.14.120 is missing patches for detecting Cascade Lake
> mitigation, Or maybe only small set of cascade lake has mitigation?
> Or the community/intel are not sure about it yet?

Did you try 4.19 or 5.1?  Try those and see if anything changes.

If not, odds are you need a microcode update from Intel, please contact
them, nothing we can do about that.

If 4.14 works different from 4.19 or 5.1, please let us know.

thanks,

greg k-h