8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 000000a0
pgd = 86cf4c80
[000000a0] *pgd=86f7d003, *pmd=e35d1003
Internal error: Oops: 207 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 1 PID: 11588 Comm: iou-sqp-11579 Not tainted 5.12.0-rc3-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at atomic_add arch/arm/include/asm/atomic.h:223 [inline]
PC is at atomic_inc include/linux/atomic-fallback.h:372 [inline]
PC is at io_uring_cancel_sqpoll+0xac/0x1a0 fs/io_uring.c:8926
LR is at io_sq_thread+0x3d0/0x6f8 fs/io_uring.c:6772
pc : [<80561f00>]    lr : [<80566f50>]    psr: 60070013
sp : 869adee0  ip : 86a2a080  fp : 869adf2c
r10: 00000000  r9 : 869ac000  r8 : 00000000
r7 : 860f4800  r6 : 85709400  r5 : 85709454  r4 : 860f4800
r3 : 000000a0  r2 : 869ac000  r1 : 000000a0  r0 : 869adef4
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 86cf4c80  DAC: 00000000
Process iou-sqp-11579 (pid: 11588, stack limit = 0x869ac210)
Stack: (0x869adee0 to 0x869ae000)
dee0: 00000000 000000a0 00000000 86a2a080 802a6878 869adef4 869adef4 56b92eae
df00: 00000001 860f4800 85709454 85709400 00000000 00000000 869ac000 00000000
df20: 869adfac 869adf30 80566f50 80561e60 85709404 81f744cc 82a06d00 00000000
df40: 80384db8 85709400 83789080 85709454 00000000 00000000 00000000 86a2a080
df60: 802a6878 869adf64 869adf64 2d756f69 2d707173 37353131 80250039 56b92eae
df80: 00000000 85709400 80566b80 00000000 00000000 00000000 00000000 00000000
dfa0: 00000000 869adfb0 80200114 80566b8c 00000000 00000000 00000000 00000000
dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
Backtrace: 
[<80561e54>] (io_uring_cancel_sqpoll) from [<80566f50>] (io_sq_thread+0x3d0/0x6f8 fs/io_uring.c:6772)
 r10:00000000 r9:869ac000 r8:00000000 r7:00000000 r6:85709400 r5:85709454
 r4:860f4800
[<80566b80>] (io_sq_thread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158)
Exception stack(0x869adfb0 to 0x869adff8)
dfa0:                                     00000000 00000000 00000000 00000000
dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80566b80
 r4:85709400
Code: e28830a0 e50b3048 f593f000 e1a01003 (e1913f9f) 
---[ end trace 2ae4d028003627ef ]---