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BUG: KCSAN: data-race in wg_packet_send_staged_packets / wg_packet_send_staged_packets

write to 0xffff88812b47da08 of 4 bytes by interrupt on cpu 1:
 wg_cpumask_next_online drivers/net/wireguard/queueing.h:134 [inline]
 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:153 [inline]
 wg_packet_create_data drivers/net/wireguard/send.c:326 [inline]
 wg_packet_send_staged_packets+0x5d9/0x9b0 drivers/net/wireguard/send.c:396
 wg_packet_send_keepalive+0x102/0x120 drivers/net/wireguard/send.c:239
 wg_expired_send_persistent_keepalive+0x38/0x50 drivers/net/wireguard/timers.c:141
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1417
 expire_timers+0x116/0x260 kernel/time/timer.c:1462
 __run_timers+0x358/0x3f0 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:629
 native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:516 [inline]
 acpi_idle_enter+0x25b/0x2e0 drivers/acpi/processor_idle.c:647
 cpuidle_enter_state+0x2b6/0x7c0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x193/0x230 kernel/sched/idle.c:299
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:396
 secondary_startup_64_no_verify+0xb0/0xbb

read to 0xffff88812b47da08 of 4 bytes by interrupt on cpu 0:
 wg_cpumask_next_online drivers/net/wireguard/queueing.h:130 [inline]
 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:153 [inline]
 wg_packet_create_data drivers/net/wireguard/send.c:326 [inline]
 wg_packet_send_staged_packets+0x595/0x9b0 drivers/net/wireguard/send.c:396
 wg_packet_send_keepalive+0x102/0x120 drivers/net/wireguard/send.c:239
 wg_expired_send_persistent_keepalive+0x38/0x50 drivers/net/wireguard/timers.c:141
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1417
 expire_timers+0x116/0x260 kernel/time/timer.c:1462
 __run_timers+0x358/0x3f0 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:629
 check_access kernel/kcsan/core.c:608 [inline]
 __kcsan_check_access+0x14/0x1b0 kernel/kcsan/core.c:792
 page_zonenum include/linux/mm.h:1101 [inline]
 is_zone_device_page include/linux/mm.h:1108 [inline]
 release_pages+0x136/0xa80 mm/swap.c:881
 free_pages_and_swap_cache+0x1db/0x1f0 mm/swap_state.c:355
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:242 [inline]
 tlb_flush_mmu+0x597/0x5f0 mm/mmu_gather.c:249
 tlb_finish_mmu+0x86/0x100 mm/mmu_gather.c:328
 exit_mmap+0x1e7/0x400 mm/mmap.c:3222
 __mmput+0xa2/0x220 kernel/fork.c:1082
 mmput+0x38/0x40 kernel/fork.c:1103
 exit_mm+0x33f/0x430 kernel/exit.c:501
 do_exit+0x41f/0x1690 kernel/exit.c:812
 do_group_exit+0xa4/0x180 kernel/exit.c:922
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:933
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:931
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:931
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17166 Comm: systemd-udevd Not tainted 5.11.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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