==================================================================
BUG: KCSAN: data-race in __io_cqring_fill_event / io_req_defer

write to 0xffff88814e81fc80 of 4 bytes by task 1614 on cpu 1:
 io_get_cqring fs/io_uring.c:1379 [inline]
 __io_cqring_fill_event+0xfd/0x350 fs/io_uring.c:1561
 io_req_complete_post+0x58/0x540 fs/io_uring.c:1585
 __io_req_complete fs/io_uring.c:1640 [inline]
 __io_complete_rw+0x3b5/0x470 fs/io_uring.c:2490
 io_complete_rw+0x1b/0x20 fs/io_uring.c:2497
 io_rw_done fs/io_uring.c:2731 [inline]
 kiocb_done+0x1b0/0x420 fs/io_uring.c:2755
 io_read fs/io_uring.c:3336 [inline]
 io_issue_sqe+0x36c5/0x6750 fs/io_uring.c:6115
 io_wq_submit_work+0x113/0x270 fs/io_uring.c:6252
 io_worker_handle_work+0x8cb/0xaf0 fs/io-wq.c:496
 io_wqe_worker+0x1c5/0x550 fs/io-wq.c:545
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff88814e81fc80 of 4 bytes by task 1612 on cpu 0:
 req_need_defer fs/io_uring.c:1208 [inline]
 io_req_defer+0x358/0x4a0 fs/io_uring.c:6002
 io_queue_sqe fs/io_uring.c:6451 [inline]
 io_submit_sqe+0x154d/0x3360 fs/io_uring.c:6626
 io_submit_sqes+0x5bd/0xbd0 fs/io_uring.c:6734
 __do_sys_io_uring_enter fs/io_uring.c:9319 [inline]
 __se_sys_io_uring_enter+0x1e1/0xa80 fs/io_uring.c:9261
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:9261
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1612 Comm: syz-executor.0 Tainted: G        W         5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 1612 Comm: syz-executor.0 Tainted: G        W         5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x137/0x19d lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail+0x23c/0x250 lib/fault-inject.c:146
 __should_failslab+0x81/0x90 mm/failslab.c:33
 should_failslab+0x5/0x20 mm/slab_common.c:1295
 slab_pre_alloc_hook mm/slab.h:499 [inline]
 slab_alloc mm/slab.c:3306 [inline]
 kmem_cache_alloc+0x46/0x2f0 mm/slab.c:3507
 kmem_cache_zalloc include/linux/slab.h:676 [inline]
 lsm_file_alloc security/security.c:571 [inline]
 security_file_alloc+0x30/0x190 security/security.c:1514
 __alloc_file+0x83/0x1a0 fs/file_table.c:106
 alloc_empty_file+0xcd/0x1c0 fs/file_table.c:150
 path_openat+0x6a/0x20b0 fs/namei.c:3480
 do_filp_open+0xd9/0x1f0 fs/namei.c:3521
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1207
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f339e122188 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 00007f339e1221d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffd899459ff R14: 00007f339e122300 R15: 0000000000022000