netdevsim netdevsim3 netdevsim0: renamed from eth0
netdevsim netdevsim3 netdevsim1: renamed from eth1
netdevsim netdevsim3 netdevsim2: renamed from eth2
netdevsim netdevsim3 netdevsim3: renamed from eth3
==================================================================
BUG: KCSAN: data-race in pcpu_alloc_noprof / pcpu_balance_workfn

read-write to 0xffffffff8841f6ac of 4 bytes by task 3179 on cpu 1:
 pcpu_update_empty_pages mm/percpu.c:602 [inline]
 pcpu_chunk_populated mm/percpu.c:1531 [inline]
 pcpu_balance_populated mm/percpu.c:2062 [inline]
 pcpu_balance_workfn+0x94e/0xa60 mm/percpu.c:2212
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x730 kernel/workqueue.c:3393
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffffffff8841f6ac of 4 bytes by task 5549 on cpu 0:
 pcpu_alloc_noprof+0x9a7/0x10c0 mm/percpu.c:1894
 fib6_nh_init+0x61a/0x15d0 net/ipv6/route.c:3628
 ip6_route_info_create+0x7b7/0xba0 net/ipv6/route.c:3809
 ip6_route_add+0x26/0x120 net/ipv6/route.c:3853
 addrconf_prefix_route net/ipv6/addrconf.c:2485 [inline]
 fixup_permanent_addr net/ipv6/addrconf.c:3600 [inline]
 addrconf_permanent_addr+0x45d/0x5e0 net/ipv6/addrconf.c:3624
 addrconf_notify+0x681/0x950 net/ipv6/addrconf.c:3696
 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:8858
 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+0x85e/0x910 net/core/rtnetlink.c:6635
 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2564
 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6653
 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: 0x00000001 -> 0x00000004

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5549 Comm: syz-executor.3 Not tainted 6.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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