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BUG: KCSAN: data-race in pcpu_alloc / pcpu_free_area

write to 0xffffffff86dc55a4 of 4 bytes by task 1838 on cpu 0:
 pcpu_update_empty_pages mm/percpu.c:606 [inline]
 pcpu_block_update_hint_free mm/percpu.c:1041 [inline]
 pcpu_free_area+0x545/0x5d0 mm/percpu.c:1298
 free_percpu+0x1c5/0x9f0 mm/percpu.c:2284
 xt_percpu_counter_free+0x5f/0x70 net/netfilter/x_tables.c:1950
 cleanup_entry+0x17a/0x1a0 net/ipv4/netfilter/ip_tables.c:656
 __do_replace+0x45e/0x580 net/ipv4/netfilter/ip_tables.c:1085
 do_replace net/ipv4/netfilter/ip_tables.c:1140 [inline]
 do_ipt_set_ctl+0x1466/0x1710 net/ipv4/netfilter/ip_tables.c:1630
 nf_setsockopt+0x1a6/0x1c0 net/netfilter/nf_sockopt.c:101
 ip_setsockopt+0x2815/0x2c80 net/ipv4/ip_sockglue.c:1444
 tcp_setsockopt+0x8c/0xa0 net/ipv4/tcp.c:3656
 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3478
 __sys_setsockopt+0x209/0x2a0 net/socket.c:2176
 __do_sys_setsockopt net/socket.c:2187 [inline]
 __se_sys_setsockopt net/socket.c:2184 [inline]
 __x64_sys_setsockopt+0x62/0x70 net/socket.c:2184
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff86dc55a4 of 4 bytes by task 25872 on cpu 1:
 pcpu_alloc+0x9c0/0xf80 mm/percpu.c:1878
 __alloc_percpu_gfp+0x22/0x30 mm/percpu.c:1937
 percpu_ref_init+0x2f/0x250 lib/percpu-refcount.c:72
 io_rsrc_node_alloc fs/io_uring.c:7767 [inline]
 io_rsrc_node_switch_start+0x71/0x110 fs/io_uring.c:7810
 io_uring_create+0x37a/0x754 fs/io_uring.c:10442
 io_uring_setup fs/io_uring.c:10524 [inline]
 __do_sys_io_uring_setup fs/io_uring.c:10530 [inline]
 __se_sys_io_uring_setup fs/io_uring.c:10527 [inline]
 __x64_sys_io_uring_setup+0x118/0x130 fs/io_uring.c:10527
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000007 -> 0x00000008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 25872 Comm: syz-executor.0 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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