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BUG: KCSAN: data-race in pcpu_alloc_noprof / pcpu_block_update_hint_alloc

read-write to 0xffffffff8841e6ac of 4 bytes by task 3101 on cpu 0:
 pcpu_update_empty_pages mm/percpu.c:602 [inline]
 pcpu_block_update_hint_alloc+0x5db/0x6a0 mm/percpu.c:923
 pcpu_alloc_area+0x488/0x4b0 mm/percpu.c:1258
 pcpu_alloc_noprof+0x4b3/0x10c0 mm/percpu.c:1834
 alloc_mem_cgroup_per_node_info mm/memcontrol.c:5651 [inline]
 mem_cgroup_alloc mm/memcontrol.c:5737 [inline]
 mem_cgroup_css_alloc+0x309/0xdc0 mm/memcontrol.c:5781
 css_create kernel/cgroup/cgroup.c:5549 [inline]
 cgroup_apply_control_enable+0x1e5/0xa00 kernel/cgroup/cgroup.c:3217
 cgroup_mkdir+0xb93/0xc70 kernel/cgroup/cgroup.c:5763
 kernfs_iop_mkdir+0x12f/0x1f0 fs/kernfs/dir.c:1246
 vfs_mkdir+0x1f4/0x320 fs/namei.c:4131
 do_mkdirat+0x12f/0x2a0 fs/namei.c:4154
 __do_sys_mkdirat fs/namei.c:4169 [inline]
 __se_sys_mkdirat fs/namei.c:4167 [inline]
 __x64_sys_mkdirat+0x50/0x60 fs/namei.c:4167
 x64_sys_call+0x2ce5/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:259
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff8841e6ac of 4 bytes by task 3114 on cpu 1:
 pcpu_alloc_noprof+0x9a7/0x10c0 mm/percpu.c:1894
 fib_nh_common_init+0x4a/0x2b0 net/ipv4/fib_semantics.c:591
 fib_nh_init+0x64/0x1b0 net/ipv4/fib_semantics.c:630
 fib_create_info+0xa26/0x1500 net/ipv4/fib_semantics.c:1497
 fib_table_insert+0x101/0xfa0 net/ipv4/fib_trie.c:1237
 fib_magic+0x1a1/0x1f0 net/ipv4/fib_frontend.c:1109
 fib_add_ifaddr+0x281/0x330 net/ipv4/fib_frontend.c:1146
 fib_netdev_event+0x34f/0x430 net/ipv4/fib_frontend.c:1491
 notifier_call_chain kernel/notifier.c:93 [inline]
 raw_notifier_call_chain+0x6f/0x1d0 kernel/notifier.c:461
 call_netdevice_notifiers_info+0xae/0x100 net/core/dev.c:1992
 __dev_notify_flags+0xff/0x1a0
 dev_change_flags+0xab/0xd0 net/core/dev.c:8857
 do_setlink+0x841/0x2490 net/core/rtnetlink.c:2900
 __rtnl_newlink net/core/rtnetlink.c:3696 [inline]
 rtnl_newlink+0x11a1/0x1690 net/core/rtnetlink.c:3743
 rtnetlink_rcv_msg+0x82e/0x8e0 net/core/rtnetlink.c:6595
 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2564
 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6613
 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
 netlink_unicast+0x58d/0x660 net/netlink/af_netlink.c:1361
 netlink_sendmsg+0x5ca/0x6e0 net/netlink/af_netlink.c:1905
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x140/0x180 net/socket.c:745
 __sys_sendto+0x1e5/0x260 net/socket.c:2192
 __do_sys_sendto net/socket.c:2204 [inline]
 __se_sys_sendto net/socket.c:2200 [inline]
 __x64_sys_sendto+0x78/0x90 net/socket.c:2200
 x64_sys_call+0x16d7/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000004 -> 0x00000003

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3114 Comm: syz-executor.0 Not tainted 6.10.0-rc2-syzkaller-00097-g2df0193e62cf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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