8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 000000a0
pgd = 872ddac0
[000000a0] *pgd=872d4003, *pmd=fe780003
Internal error: Oops: 207 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 8276 Comm: iou-sqp-8270 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: 60000013
sp : 8609dee0  ip : 872ec100  fp : 8609df2c
r10: 00000000  r9 : 8609c000  r8 : 00000000
r7 : 87896000  r6 : 873c7300  r5 : 873c7354  r4 : 87896000
r3 : 000000a0  r2 : 8609c000  r1 : 000000a0  r0 : 8609def4
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 30c5387d  Table: 872ddac0  DAC: fffffffd
Process iou-sqp-8270 (pid: 8276, stack limit = 0x8609c210)
Stack: (0x8609dee0 to 0x8609e000)
dee0: 00000000 000000a0 00000000 872ec100 802a6878 8609def4 8609def4 56b92eae
df00: 00000001 87896000 873c7354 873c7300 00000000 00000000 8609c000 00000000
df20: 8609dfac 8609df30 80566f50 80561e60 873c7304 81f744cc 82a06d00 00000000
df40: 80384db8 873c7300 871dac00 873c7354 00000000 00000000 00000000 872ec100
df60: 802a6878 8609df64 8609df64 2d756f69 2d707173 30373238 80258400 56b92eae
df80: 00000000 873c7300 80566b80 00000000 00000000 00000000 00000000 00000000
dfa0: 00000000 8609dfb0 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 r9:8609c000 r8:00000000 r7:00000000 r6:873c7300 r5:873c7354
 r4:87896000
[<80566b80>] (io_sq_thread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158)
Exception stack(0x8609dfb0 to 0x8609dff8)
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
 r4:873c7300
Code: e28830a0 e50b3048 f593f000 e1a01003 (e1913f9f) 
---[ end trace 91f2ab2a99e960ea ]---