Restart at boot with new kernel

Hi list,

just compiled current and after reboot into the new kernel the machine
reboots itself at the marked line below. No further info as the reset is
sudden. Reboot with the old kernel from 12 aug works. Removed all kernel
modules but with no result.

Any pointers how to approach this?

Aug 14 21:35:19 workstation kernel: ---<<BOOT>>---
Aug 14 21:35:19 workstation kernel: Copyright (c) 1992-2018 The FreeBSD
Project.
Aug 14 21:35:19 workstation kernel: Copyright (c) 1979, 1980, 1983, 1986,
1988, 1989, 1991, 1992, 1993, 1994
Aug 14 21:35:19 workstation kernel:     The Regents of the University of
California. All rights reserved.
Aug 14 21:35:19 workstation kernel: FreeBSD is a registered trademark of
The FreeBSD Foundation.
Aug 14 21:35:19 workstation kernel: FreeBSD 12.0-ALPHA1 #9
8501082ee8a(master): Tue Aug 14 21:13:15 CEST 2018
Aug 14 21:35:19 workstation kernel:
root_at_workstation:/usr/obj/usr/src/amd64.amd64/sys/GENERIC-NODEBUG
amd64
Aug 14 21:35:19 workstation kernel: FreeBSD clang version 6.0.1
(tags/RELEASE_601/final 335540) (based on LLVM 6.0.1)
Aug 14 21:35:19 workstation kernel: VT(efifb): resolution 1024x768
Aug 14 21:35:19 workstation kernel: CPU: Intel(R) Core(TM) i7-2600K CPU _at_
3.40GHz (3410.09-MHz K8-class CPU)
Aug 14 21:35:19 workstation kernel:   Origin="GenuineIntel"  Id=0x206a7
Family=0x6  Model=0x2a  Stepping=7
Aug 14 21:35:19 workstation kernel:
Features=0xbfebfbff<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,HTT,TM,PBE>
Aug 14 21:35:19 workstation kernel:
Features2=0x1f9ae3bf<SSE3,PCLMULQDQ,DTES64,MON,DS_CPL,VMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,POPCNT,TSCDLT,AESNI,XSAVE,OSXSAVE,AVX>
Aug 14 21:35:19 workstation kernel:   AMD
Features=0x28100800<SYSCALL,NX,RDTSCP,LM>
Aug 14 21:35:19 workstation kernel:   AMD Features2=0x1<LAHF>
Aug 14 21:35:19 workstation kernel:   XSAVE Features=0x1<XSAVEOPT>
Aug 14 21:35:19 workstation kernel:   VT-x: PAT,HLT,MTF,PAUSE,EPT,UG,VPID
Aug 14 21:35:19 workstation kernel:   TSC: P-state invariant, performance
statistics
Aug 14 21:35:19 workstation kernel: real memory  = 34359738368 (32768 MB)
Aug 14 21:35:19 workstation kernel: avail memory = 33333342208 (31789 MB)
Aug 14 21:35:19 workstation kernel: Event timer "LAPIC" quality 600
Aug 14 21:35:19 workstation kernel: ACPI APIC Table: <ALASKA A M I>
Aug 14 21:35:19 workstation kernel: FreeBSD/SMP: Multiprocessor System
Detected: 8 CPUs
Aug 14 21:35:19 workstation kernel: FreeBSD/SMP: 1 package(s) x 4 core(s) x
2 hardware threads
Aug 14 21:35:19 workstation kernel: random: unblocking device.
Aug 14 21:35:19 workstation kernel: ioapic0 <Version 2.0> irqs 0-23 on
motherboard
>> REBOOT Aug 14 21:35:19 workstation kernel: Launching APs: 1 7 3 6 4 5
---<<BOOT>>---
Aug 14 21:35:19 workstation kernel: Copyright (c) 1992-2018 The FreeBSD
Project........