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BUG: KCSAN: data-race in __mod_timer / expire_timers

write to 0xffff88813bc1b908 of 8 bytes by interrupt on cpu 0:
 expire_timers+0x11e/0x260 kernel/time/timer.c:1477
 __run_timers+0x358/0x3f0 kernel/time/timer.c:1745
 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1758
 __do_softirq+0x13c/0x2c3 kernel/softirq.c:343
 asm_call_irq_on_stack+0xf/0x20
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:226 [inline]
 __irq_exit_rcu+0xb4/0xc0 kernel/softirq.c:420
 sysvec_apic_timer_interrupt+0x74/0x90 arch/x86/kernel/apic/apic.c:1100
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635
 console_unlock+0x8c9/0xb20 kernel/printk/printk.c:2573
 vprintk_emit+0x131/0x3e0 kernel/printk/printk.c:2092
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2109
 vprintk_func+0x11b/0x120 kernel/printk/printk_safe.c:393
 printk+0x62/0x82 kernel/printk/printk.c:2140
 batadv_hardif_enable_interface+0x747/0x7c0 net/batman-adv/hard-interface.c:781
 batadv_softif_slave_add+0x74/0xf0 net/batman-adv/soft-interface.c:858
 do_set_master net/core/rtnetlink.c:2519 [inline]
 do_setlink+0x87d/0x2280 net/core/rtnetlink.c:2715
 __rtnl_newlink net/core/rtnetlink.c:3376 [inline]
 rtnl_newlink+0xe7e/0x1310 net/core/rtnetlink.c:3491
 rtnetlink_rcv_msg+0x728/0x7c0 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x13e/0x240 net/netlink/af_netlink.c:2502
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5571
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x5fc/0x6c0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x6f8/0x7c0 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0x2a8/0x370 net/socket.c:1975
 __do_sys_sendto net/socket.c:1987 [inline]
 __se_sys_sendto net/socket.c:1983 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:1983
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88813bc1b908 of 8 bytes by task 24 on cpu 1:
 __mod_timer+0x44e/0xc10 kernel/time/timer.c:1035
 add_timer+0x38/0x50 kernel/time/timer.c:1142
 __queue_delayed_work+0xec/0x150 kernel/workqueue.c:1655
 queue_delayed_work_on+0x6f/0xd0 kernel/workqueue.c:1680
 queue_delayed_work include/linux/workqueue.h:522 [inline]
 bond_netdev_notify_work+0x14a/0x170 drivers/net/bonding/bond_main.c:1574
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x616/0xa70 kernel/workqueue.c:2421
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 24 Comm: kworker/u4:1 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bond0 bond_netdev_notify_work
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