(posted in discord #kernel channel before, repost to here for filing)

debug log:

[#0 SyncTask(3:3)]: Ext2FS: Flushed 8 blocks to disk
Triple fault
CPU Reset (CPU 0)
EAX=0a8bb000 EBX=c10b34f8 ECX=c10b4088 EDX=c10b5640
ESI=c10b56c0 EDI=c6562290 EBP=c642e5fc ESP=c642e5fc
EIP=c08185bf EFL=00000092 [--S-A--] CPL=0 II=0 A20=1 SMM=0 HLT=0
ES =0010 00000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
CS =0008 00000000 ffffffff 00cf9a00 DPL=0 CS32 [-R-]
SS =0010 00000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
DS =0010 00000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
FS =0023 00000000 ffffffff 00cff300 DPL=3 DS   [-WA]
GS =0030 c10b56c0 0000094f 00409300 DPL=0 DS   [-WA]
LDT=0000 00000000 0000ffff 00008200 DPL=0 LDT
TR =0038 c10b5edc 00000067 00408900 DPL=0 TSS32-avl
GDT=     c10b56ca 0000003f
IDT=     c10b40a0 000007ff
CR0=80010013 CR2=c10b40e0 CR3=0a8bb000 CR4=003406e4
DR0=00000000 DR1=00000000 DR2=00000000 DR3=00000000
DR6=ffff0ff0 DR7=00000400
CCS=0000000c CCD=c642e608 CCO=SUBL
EFER=0000000000000800
FCW=037f FSW=0020 [ST=0] FTW=00 MXCSR=00001f80
FPR0=0000000000000000 0000 FPR1=0000000000000000 0000
FPR2=0000000000000000 0000 FPR3=0000000000000000 0000
FPR4=0000000000000000 0000 FPR5=0000000000000000 0000
FPR6=e000000000000000 4002 FPR7=83dc0c0d73f05c10 4004

kaddr2line:

roy@ubuntu2004lts:~/serenity$ Meta/serenity.sh kaddr2line i686 0x6185bf
ninja: Entering directory `/home/roy/serenity/Build/i686'
[0/2] Re-checking globbed directories...
[1/1] cd /home/roy/serenity/Build/i686/Userland/Libraries/...roy/serenity/Build/i686/Userland/Libraries/LibC/libc.a *.o
./Build/i686/../../Kernel/Arch/x86/i386/ASM_wrapper.cpp:52

--

A step-by-step for reproducing this bug:

• run Meta/serenity.sh build to build whole system, then run Meta/serenity.sh run for first run, then shut it down
• compile Ports/gcc, Ports/ed , Ports/mawk , Ports/sed , Ports/grep and Ports/bash for perl Configure use
• replace /bin/sh with bash
• grab perl-5.34.0 from cpan: https://www.cpan.org/src/5.0/perl-5.34.0.tar.gz
• extract it to /home/anon (better to do this outside VM since it is way faster than doing it inside VM)
  create /home/anon/perl-5.34.0/hints/serenityos.sh with following contents:

libs='-ldl -lm -lcrypt -lcore'

# Use OS's malloc() by default.
case "$usemymalloc" in
'') usemymalloc='n' ;;
esac

# uses gcc.
cc="gcc"
ld='gcc'

# as of the latest some symbols are confusing the nm lookup
case "$usenm" in
'') usenm='undef' ;;
esac

• boot up VM,
• run cd /home/anon/perl-5.34.0; bash Configure -de