panic: ASan: Invalid access, 8-byte write at 0xffffffff84c18980, GenericRedZone(fa)
cpuid = 0
time = 1
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0xc6/frame 0xffffffff84c18470
kdb_backtrace() at kdb_backtrace+0xd0/frame 0xffffffff84c185d0
vpanic() at vpanic+0x280/frame 0xffffffff84c18790
panic() at panic+0xb5/frame 0xffffffff84c18860
kasan_report() at kasan_report+0xdf/frame 0xffffffff84c18930
pctrie_remove_lookup() at pctrie_remove_lookup+0xf8/frame 0xffffffff84c189f0
pmap_demote_pde_locked() at pmap_demote_pde_locked+0x323/frame 0xffffffff84c18bf0
pmap_change_props_locked() at pmap_change_props_locked+0x896/frame 0xffffffff84c18d90
pmap_init() at pmap_init+0xddd/frame 0xffffffff84c18eb0
vm_mem_init() at vm_mem_init+0xa8/frame 0xffffffff84c18ed0
mi_startup() at mi_startup+0x2c9/frame 0xffffffff84c18ff0
KDB: enter: panic
[ thread pid 0 tid 0 ]
Stopped at      kdb_enter+0x6e: movq    $0,0x23e2e77(%rip)
db> serialport: Connected to syzkaller.us-central1-b.ci-freebsd-main-test-0 port 1 (session ID: b6f7b38458fa5b90981a85c544f21c49596b3c5b4ea8c357a83dbb177b454bfd, active connections: 1).