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BUG: KCSAN: data-race in __mod_timer / expire_timers

write to 0xffff88813bc1bd88 of 8 bytes by interrupt on cpu 0:
 expire_timers+0x164/0x260 kernel/time/timer.c:1458
 __run_timers+0x338/0x3d0 kernel/time/timer.c:1731
 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1744
 __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:1096
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628
 native_restore_fl arch/x86/include/asm/irqflags.h:41 [inline]
 arch_local_irq_restore arch/x86/include/asm/irqflags.h:84 [inline]
 console_trylock_spinning kernel/printk/printk.c:1805 [inline]
 vprintk_emit+0x210/0x360 kernel/printk/printk.c:2091
 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
 __ip_vs_ftp_init+0x13d/0x1b0 net/netfilter/ipvs/ip_vs_ftp.c:594
 ops_init+0x1e7/0x230 net/core/net_namespace.c:152
 setup_net+0x12b/0x640 net/core/net_namespace.c:342
 copy_net_ns+0x2a9/0x450 net/core/net_namespace.c:483
 create_new_namespaces+0x231/0x560 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xe2/0x120 kernel/nsproxy.c:226
 ksys_unshare+0x38a/0x690 kernel/fork.c:2955
 __do_sys_unshare kernel/fork.c:3023 [inline]
 __se_sys_unshare kernel/fork.c:3021 [inline]
 __x64_sys_unshare+0x1b/0x20 kernel/fork.c:3021
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88813bc1bd88 of 8 bytes by task 11422 on cpu 1:
 __mod_timer+0x442/0xbf0 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+0x78/0xc0 kernel/workqueue.c:1680
 queue_delayed_work include/linux/workqueue.h:522 [inline]
 bond_mii_monitor+0x1594/0x1620 drivers/net/bonding/bond_main.c:2528
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x64a/0xaa0 kernel/workqueue.c:2421
 kthread+0x1fd/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11422 Comm: kworker/u4:5 Not tainted 5.11.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bond3 bond_mii_monitor
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