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BUG: KCSAN: data-race in mem_cgroup_flush_stats_ratelimited / tick_do_update_jiffies64

read-write to 0xffffffff86c09a00 of 8 bytes by interrupt on cpu 0:
 tick_do_update_jiffies64+0x113/0x1c0 kernel/time/tick-sched.c:118
 tick_sched_do_timer kernel/time/tick-sched.c:253 [inline]
 tick_nohz_handler+0x8d/0x3d0 kernel/time/tick-sched.c:312
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x218/0x4f0 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1f0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 ip_finish_output2+0x4/0x8c0 net/ipv4/ip_output.c:201
 __ip_finish_output net/ipv4/ip_output.c:-1 [inline]
 ip_finish_output+0x112/0x290 net/ipv4/ip_output.c:325
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0xbd/0x1c0 net/ipv4/ip_output.c:438
 dst_output include/net/dst.h:470 [inline]
 ip_local_out+0xaa/0xd0 net/ipv4/ip_output.c:131
 iptunnel_xmit+0x3d8/0x6a0 net/ipv4/ip_tunnel_core.c:97
 udp_tunnel_xmit_skb+0x1bd/0x220 net/ipv4/udp_tunnel_core.c:193
 send4+0x4de/0x5c0 drivers/net/wireguard/socket.c:85
 wg_socket_send_skb_to_peer+0x95/0x130 drivers/net/wireguard/socket.c:175
 wg_socket_send_buffer_to_peer+0xf1/0x120 drivers/net/wireguard/socket.c:200
 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline]
 wg_packet_handshake_send_worker+0x10d/0x160 drivers/net/wireguard/send.c:51
 process_one_work kernel/workqueue.c:3276 [inline]
 process_scheduled_works+0x513/0xa10 kernel/workqueue.c:3359
 worker_thread+0x58a/0x780 kernel/workqueue.c:3440
 kthread+0x22a/0x280 kernel/kthread.c:436
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffffffff86c09a00 of 8 bytes by task 6813 on cpu 1:
 mem_cgroup_flush_stats_ratelimited+0x29/0x70 mm/memcontrol.c:638
 count_shadow_nodes+0x6a/0x230 mm/workingset.c:678
 do_shrink_slab+0x63/0x6a0 mm/shrinker.c:384
 shrink_slab_memcg mm/shrinker.c:550 [inline]
 shrink_slab+0x538/0x880 mm/shrinker.c:628
 shrink_node_memcgs mm/vmscan.c:6022 [inline]
 shrink_node+0x6bc/0x2130 mm/vmscan.c:6061
 shrink_zones mm/vmscan.c:6300 [inline]
 do_try_to_free_pages+0x408/0xc80 mm/vmscan.c:6362
 try_to_free_mem_cgroup_pages+0x1f5/0x470 mm/vmscan.c:6683
 try_charge_memcg+0x37e/0xa10 mm/memcontrol.c:2414
 try_charge mm/memcontrol.c:2556 [inline]
 charge_memcg mm/memcontrol.c:4744 [inline]
 mem_cgroup_swapin_charge_folio+0x103/0x1f0 mm/memcontrol.c:4830
 __swap_cache_prepare_and_add+0x67/0x460 mm/swap_state.c:498
 swap_cache_alloc_folio+0xa2/0x120 mm/swap_state.c:574
 swap_cluster_readahead+0x26e/0x3d0 mm/swap_state.c:748
 swapin_readahead+0xde/0x840 mm/swap_state.c:923
 do_swap_page+0x2fe/0x21e0 mm/memory.c:4802
 handle_pte_fault mm/memory.c:6320 [inline]
 __handle_mm_fault mm/memory.c:6455 [inline]
 handle_mm_fault+0xb46/0x3020 mm/memory.c:6624
 do_user_addr_fault+0x62f/0x1050 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618

value changed: 0x00000000ffffb133 -> 0x00000000ffffb134

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6813 Comm: syz.3.1084 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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