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BUG: KCSAN: data-race in wg_packet_send_staged_packets / wg_packet_send_staged_packets

write to 0xffff8881389e9a48 of 4 bytes by interrupt on cpu 0:
 wg_cpumask_next_online drivers/net/wireguard/queueing.h:135 [inline]
 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:178 [inline]
 wg_packet_create_data drivers/net/wireguard/send.c:320 [inline]
 wg_packet_send_staged_packets+0x455/0x800 drivers/net/wireguard/send.c:387
 wg_packet_send_keepalive+0xfc/0x110 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:1421
 expire_timers+0x116/0x240 kernel/time/timer.c:1466
 __run_timers+0x368/0x410 kernel/time/timer.c:1734
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1747
 __do_softirq+0x158/0x2de kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x37/0x70 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20

read to 0xffff8881389e9a48 of 4 bytes by interrupt on cpu 1:
 wg_cpumask_next_online drivers/net/wireguard/queueing.h:131 [inline]
 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:178 [inline]
 wg_packet_create_data drivers/net/wireguard/send.c:320 [inline]
 wg_packet_send_staged_packets+0x41a/0x800 drivers/net/wireguard/send.c:387
 wg_packet_send_keepalive+0xfc/0x110 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:1421
 expire_timers+0x116/0x240 kernel/time/timer.c:1466
 __run_timers+0x368/0x410 kernel/time/timer.c:1734
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1747
 __do_softirq+0x158/0x2de kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x37/0x70 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 is_atomic kernel/kcsan/core.c:238 [inline]
 should_watch kernel/kcsan/core.c:266 [inline]
 check_access kernel/kcsan/core.c:633 [inline]
 __tsan_read8+0x11a/0x180 kernel/kcsan/core.c:855
 folio_memcg_kmem include/linux/memcontrol.h:536 [inline]
 folio_memcg include/linux/memcontrol.h:443 [inline]
 folio_memcg_unlock mm/memcontrol.c:2093 [inline]
 unlock_page_memcg+0x2e/0xe0 mm/memcontrol.c:2099
 page_remove_rmap+0x1de/0x230 mm/rmap.c:1387
 zap_pte_range+0x708/0x10e0 mm/memory.c:1357
 zap_pmd_range mm/memory.c:1467 [inline]
 zap_pud_range mm/memory.c:1496 [inline]
 zap_p4d_range mm/memory.c:1517 [inline]
 unmap_page_range+0x2dc/0x3d0 mm/memory.c:1538
 unmap_single_vma+0x157/0x210 mm/memory.c:1583
 unmap_vmas+0xd0/0x180 mm/memory.c:1615
 exit_mmap+0x23d/0x470 mm/mmap.c:3170
 __mmput+0x27/0x1b0 kernel/fork.c:1113
 mmput+0x3d/0x50 kernel/fork.c:1134
 exit_mm+0xdb/0x170 kernel/exit.c:507
 do_exit+0x608/0x17a0 kernel/exit.c:819
 do_group_exit+0x17d/0x180 kernel/exit.c:929
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:940
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:938
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:938
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23720 Comm: syz-executor.2 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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