12.0-ALPHA6 dumps with 'Fatal double fault'

[Michael Schmiedgen]

> Can you elaborate which port was triggering the fault and which platform you are using?
> I would like to reproduce the issue and fix it.

Port is devel/apr1 and platform is amd64.

CPU: Intel(R) Xeon(R) CPU E31245 @ 3.30GHz (3300.10-MHz K8-class CPU)
   Origin="GenuineIntel"  Id=0x206a7  Family=0x6  Model=0x2a  Stepping=7
   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>
Features2=0x1fbae3ff<SSE3,PCLMULQDQ,DTES64,MON,DS_CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,TSCDLT,AESNI,XSAVE,OSXSAVE,AVX>
   AMD Features=0x28100800<SYSCALL,NX,RDTSCP,LM>
   AMD Features2=0x1<LAHF>
   XSAVE Features=0x1<XSAVEOPT>
   VT-x: PAT,HLT,MTF,PAUSE,EPT,UG,VPID
   TSC: P-state invariant, performance statistics

It crashed multiple times randomly under heavy load when compiling ports. But I
observed a crash two times exactly in the same place: configure script SCTP test
in devel/apr1.

Thanks,
   Michael