Some (but not all, for added fun) Launchpad builders have these CPUs:

processor       : 0
vendor_id       : AuthenticAMD
cpu family      : 23
model           : 1
model name      : AMD EPYC 7351 16-Core Processor
stepping        : 2
microcode       : 0x1000065
cpu MHz         : 2395.494
cache size      : 512 KB
physical id     : 0
siblings        : 1
core id         : 0
cpu cores       : 1
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 13
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm rep_good nopl cpuid extd_apicid tsc_known_freq pni pclmulqdq ssse3 fma cx16 sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm cmp_legacy svm cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ssbd ibpb vmmcall fsgsbase tsc_adjust bmi1 avx2 smep bmi2 rdseed adx smap clflushopt xsaveopt xsavec xgetbv1 virt_ssbd arat npt nrip_save
bugs            : fxsave_leak sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips        : 4790.98
TLB size        : 1024 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 40 bits physical, 48 bits virtual
power management:

And on these CPUs elf/tst-cpu-features-cpuinfo-static fails like this:

Checking HAS_CPU_FEATURE (AMD_SSBD):
  HAS_CPU_FEATURE (AMD_SSBD): 0
  cpuinfo (ssbd): 1
 *** failure ***

This seems to be the same failure as https://sourceware.org/pipermail/libc-alpha/2021-February/122227.html but I'm not sure there was any follow up to that mail.