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Unable to handle kernel NULL pointer dereference at virtual address 000000a0
pgd = 86d35900
[000000a0] *pgd=8701f003, *pmd=fe695003
Internal error: Oops: 207 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 7640 Comm: iou-sqp-7630 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 : 86f85ee0  ip : 834f4100  fp : 86f85f2c
r10: 00000000  r9 : 86f84000  r8 : 00000000
r7 : 86e7c800  r6 : 85b17400  r5 : 85b17454  r4 : 86e7c800
r3 : 000000a0  r2 : 86f84000  r1 : 000000a0  r0 : 86f85ef4
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 30c5387d  Table: 86d35900  DAC: fffffffd
Process iou-sqp-7630 (pid: 7640, stack limit = 0x86f84210)
Stack: (0x86f85ee0 to 0x86f86000)
5ee0: 00000000 000000a0 00000000 834f4100 802a6878 86f85ef4 86f85ef4 56b92eae
5f00: 00000001 86e7c800 85b17454 85b17400 00000000 00000000 86f84000 00000000
5f20: 86f85fac 86f85f30 80566f50 80561e60 85b17404 81f744cc 82a06d00 00000000
5f40: 80384db8 85b17400 835e1080 85b17454 00000000 00000000 00000000 834f4100
5f60: 802a6878 86f85f64 86f85f64 2d756f69 2d707173 30333637 80258400 56b92eae
5f80: 00000000 85b17400 80566b80 00000000 00000000 00000000 00000000 00000000
5fa0: 00000000 86f85fb0 80200114 80566b8c 00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 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 r9:86f84000 r8:00000000 r7:00000000 r6:85b17400 r5:85b17454
 r4:86e7c800
[<80566b80>] (io_sq_thread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158)
Exception stack(0x86f85fb0 to 0x86f85ff8)
5fa0:                                     00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80566b80
 r4:85b17400
Code: e28830a0 e50b3048 f593f000 e1a01003 (e1913f9f) 
---[ end trace 30197fcc0479e86d ]---