8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 000000a0 pgd = 86d57840 [000000a0] *pgd=86c93003, *pmd=e4508003 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 4882 Comm: iou-sqp-4874 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 : 86287ee0 ip : 834f6180 fp : 86287f2c r10: 00000000 r9 : 86286000 r8 : 00000000 r7 : 863c2000 r6 : 86d37000 r5 : 86d37054 r4 : 863c2000 r3 : 000000a0 r2 : 86286000 r1 : 000000a0 r0 : 86287ef4 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 86d57840 DAC: 00000000 Process iou-sqp-4874 (pid: 4882, stack limit = 0x86286210) Stack: (0x86287ee0 to 0x86288000) 7ee0: 00000000 000000a0 00000000 834f6180 802a6878 86287ef4 86287ef4 56b92eae 7f00: 00000001 863c2000 86d37054 86d37000 00000000 00000000 86286000 00000000 7f20: 86287fac 86287f30 80566f50 80561e60 86d37004 81f744cc 82a06d00 00000000 7f40: 80384db8 86d37000 84279080 86d37054 00000000 00000000 00000000 834f6180 7f60: 802a6878 86287f64 86287f64 2d756f69 2d707173 34373834 80258400 56b92eae 7f80: 00000000 86d37000 80566b80 00000000 00000000 00000000 00000000 00000000 7fa0: 00000000 86287fb0 80200114 80566b8c 00000000 00000000 00000000 00000000 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7fe0: 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 r9:86286000 r8:00000000 r7:00000000 r6:86d37000 r5:86d37054 r4:863c2000 [<80566b80>] (io_sq_thread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158) Exception stack(0x86287fb0 to 0x86287ff8) 7fa0: 00000000 00000000 00000000 00000000 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80566b80 r4:86d37000 Code: e28830a0 e50b3048 f593f000 e1a01003 (e1913f9f) ---[ end trace 6e4a71e180939dfc ]---