Fatal trap NUM: page fault while in kernel mode (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fb05f761ac0b siftr: remove the shutdown_pre_sync event han..
git tree: freebsd-src
console output: https://syzkaller.appspot.com/x/log.txt?x=158c05fd980000
dashboard link: https://syzkaller.appspot.com/bug?extid=64ccce81ff5f7b695b06

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+64ccce...@syzkaller.appspotmail.com

Fatal trap 12: page fault while in kernel mode
cpuid = 1; apic id = 01
fault virtual address = 0x0
fault code = supervisor read data, page not present
instruction pointer = 0x20:0xffffffff81a265e3
stack pointer = 0x28:0xfffffe0056c8a1c0
SYZFAIL: failed to recv rpc
fd=3 want=4 recv=0 n=0 (errno 9: Bad file descriptor)
frame pointer = 0x28:0xfffffe0056c8a6f0
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = interrupt enabled, resume, IOPL = 0
current process = 2 (clock (0))
rdi: 0000000000000000 rsi: 0000000000000000 rdx: 0000000000f6df60
rcx: fffffe00033eee30 r8: 0000000000000000 r9: 00000000060080fe
rax: fffffe00033eee30 rbx: fffffe006d1740e0 rbp: fffffe0056c8a6f0

r10: aa02000000000000 r11: 000000000000001f r12: fffffe0056c8a4c0
r13: fffffe0056c8a500 r14: 0000000000000000 r15: fffffe00829b7338
trap number = 12


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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: c7bc30c24f86 stress2: Some tests use hw.ncpu to scale the ..
git tree: freebsd-src
console output: https://syzkaller.appspot.com/x/log.txt?x=17b69d83980000
dashboard link: https://syzkaller.appspot.com/bug?extid=64ccce81ff5f7b695b06
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=162f17d3980000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+64ccce...@syzkaller.appspotmail.com

Fatal trap 12: page fault while in kernel mode

cpuid = 0; apic id = 00

fault virtual address = 0x0
fault code = supervisor read data, page not present

instruction pointer = 0x20:0xffffffff81a27ea3

stack pointer = 0x28:0xfffffe0056c8a1c0

frame pointer = 0x28:0xfffffe0056c8a6f0
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = interrupt enabled, resume, IOPL = 0
current process = 2 (clock (0))

rdi: 0000000000000000 rsi: 0000000000000000 rdx: 000000000dc8c760

rcx: fffffe00033eee30 r8: 0000000000000000 r9: 00000000060080fe

rax: fffffe00033eee30 rbx: fffffe006dc79ce0 rbp: fffffe0056c8a6f0
r10: aa03000000000000 r11: 000000000000001f r12: fffffe0056c8a4c0
if_delmulti_locked: detaching ifnet instance 0xfffffe006e463000

r13: fffffe0056c8a500 r14: 0000000000000000 r15: fffffe00829b7338

trap number = 12


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