Panic on boot with r351461 (AMD ThreadRipper 2990WX)

I updated my kernel to r351461 today and now get a panic on boot.


CPU: AMD Ryzen Threadripper 2990WX 32-Core Processor (2994.45-MHz
K8-class CPU)
  Origin="AuthenticAMD"  Id=0x800f82  Family=0x17  Model=0x8  Stepping=2
 
Features=0x178bfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,MMX,FXSR,SSE,SSE2,HTT>
 
Features2=0x7ed8320b<SSE3,PCLMULQDQ,MON,SSSE3,FMA,CX16,SSE4.1,SSE4.2,MOVBE,POPCNT,AESNI,XSAVE,OSXSAVE,AVX,F16C,RDRAND>
  AMD Features=0x2e500800<SYSCALL,NX,MMX+,FFXSR,Page1GB,RDTSCP,LM>
  AMD
Features2=0x35c233ff<LAHF,CMP,SVM,ExtAPIC,CR8,ABM,SSE4A,MAS,Prefetch,OSVW,SKINIT,WDT,TCE,Topology,PCXC,PNXC,DBE,PL2I,MWAITX>
  Structured Extended
Features=0x209c01a9<FSGSBASE,BMI1,AVX2,SMEP,BMI2,RDSEED,ADX,SMAP,CLFLUSHOPT,SHA>
  XSAVE Features=0xf<XSAVEOPT,XSAVEC,XINUSE,XSAVES>
  AMD Extended Feature Extensions ID
EBX=0x1007<CLZERO,IRPerf,XSaveErPtr,IBPB>
  SVM: NP,NRIP,VClean,AFlush,DAssist,NAsids=32768
  TSC: P-state invariant, performance statistics
real memory  = 137438953472 (131072 MB)
avail memory = 133711564800 (127517 MB)
Event timer "LAPIC" quality 600
ACPI APIC Table: <AMD A M I >

Fatal trap 12: page fault while in kernel mode

cpuid = 0; apic id = 00

fault virtual address   = 0x30

fault code  = supervisor read data, page not present

instruction pointer = 0x20: 0xffffffff811bc664

stack pointer = 0x28:0xffffffff8441faa0

frame pointer = 0x28:0xffffffff8441fae0

code segment = base 0x0, limit 0xfffff, type 0x1b

  = DPL 0, pres 1, long 1, def32 0, gran 1

processor eflags = resume, IOPL = 0

current process = 0 ()

tral number = 12

panic: page fault

cpuid = 0

time = 1

KDB: stack backtrace:

db_trace_self_wrapper()

...

--- trap 0xc, rip = 0xffffffff811bc664, rsp = 0xffffffff8441faa0, rbp =
0xffffffff8441fae0 ---

native_start_all_aps()

cpu_mp_start()

mp_start()

mi_startup()


-- 
Rebecca Cran