freebsd test error: Fatal trap NUM: page fault while in kernel mode

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2a21cfe60fcf pctrie: avoid typecast
git tree: freebsd-src
console output: https://syzkaller.appspot.com/x/log.txt?x=15961e0e980000
dashboard link: https://syzkaller.appspot.com/bug?extid=1097ef4cee8dfb240e31

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1097ef...@syzkaller.appspotmail.com

Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address = 0xfffff7800067ddca
fault code = supervisor read data, page not present
instruction pointer = 0x20:0xffffffff81578703
stack pointer = 0x28:0xffffffff84bfdce0
frame pointer = 0x28:0xffffffff84bfdce0
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 ()
rdi: fffffe00033eee50 rsi: 0000000000000007 rdx: 000000000067ddca
rcx: fffffe00033eee57 r8: 0000000000000000 r9: 0000000000000000
rax: fffff78000000000 rbx: fffffe00033eee30 rbp: ffffffff84bfdce0
r10: 0000000000000000 r11: 0000000000000000 r12: 000000007fd5f000
r13: ffffffff83aa8880 r14: 0000000000000000 r15: 0000000000000005
trap number = 12
panic: page fault
cpuid = 0
time = 1
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0xc6/frame 0xffffffff84bfd410
kdb_backtrace() at kdb_backtrace+0xd0/frame 0xffffffff84bfd570
vpanic() at vpanic+0x280/frame 0xffffffff84bfd730
panic() at panic+0xb5/frame 0xffffffff84bfd7f0
trap_fatal() at trap_fatal+0x7f2/frame 0xffffffff84bfd910
trap_pfault() at trap_pfault+0x179/frame 0xffffffff84bfda30
trap() at trap+0x648/frame 0xffffffff84bfdc10
calltrap() at calltrap+0x8/frame 0xffffffff84bfdc10
--- trap 0xc, rip = 0xffffffff81578703, rsp = 0xffffffff84bfdce0, rbp = 0xffffffff84bfdce0 ---
__asan_store8_noabort() at __asan_store8_noabort+0x83/frame 0xffffffff84bfdce0
vm_page_init_page() at vm_page_init_page+0x25/frame 0xffffffff84bfdd10
vm_phys_enqueue_contig() at vm_phys_enqueue_contig+0x6f1/frame 0xffffffff84bfdd90
vm_page_startup() at vm_page_startup+0x1805/frame 0xffffffff84bfdeb0
vm_mem_init() at vm_mem_init+0x2d/frame 0xffffffff84bfded0
mi_startup() at mi_startup+0x2d9/frame 0xffffffff84bfdff0
KDB: enter: panic
[ thread pid 0 tid 0 ]
Stopped at kdb_enter+0x6e: movq $0,0x23cd5c7(%rip)
db> serialport: Connected to syzkaller.us-central1-b.ci-freebsd-main-test-0 port 1 (session ID: 5810fe282e1cbced0efcc98e20626b435aa87cbe02d18d1252bae93f7fc31753, active connections: 1).


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