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oom-kill:constraint=CONSTRAINT_MEMCG,nodemask=(null),cpuset=/,mems_allowed=0,oom_memcg=/syz0,task_memcg=/syz0,task=syz.0.6607,pid=29237,uid=0
Memory cgroup out of memory: Killed process 29237 (syz.0.6607) total-vm:98536kB, anon-rss:1228kB, file-rss:26636kB, shmem-rss:0kB, UID:0 pgtables:156kB oom_score_adj:1000
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BUG: KCSAN: data-race in mem_cgroup_flush_stats_ratelimited / tick_do_update_jiffies64

read-write to 0xffffffff86c07a00 of 8 bytes by interrupt on cpu 1:
 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:1930 [inline]
 __hrtimer_run_queues+0x276/0x4f0 kernel/time/hrtimer.c:1994
 hrtimer_interrupt+0x261/0x850 kernel/time/hrtimer.c:2113
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1c0 arch/x86/kernel/apic/apic.c:1067
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
 console_flush_all+0x540/0x6c0 kernel/printk/printk.c:3343
 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
 console_unlock+0xa1/0x280 kernel/printk/printk.c:3413
 vprintk_emit+0x3e4/0x600 kernel/printk/printk.c:2479
 dev_vprintk_emit+0x242/0x2a0 drivers/base/core.c:4930
 dev_printk_emit+0x84/0xb0 drivers/base/core.c:4941
 __netdev_printk+0x34b/0x370 net/core/dev.c:12941
 netdev_info+0xa6/0xd0 net/core/dev.c:12996
 nsim_udp_tunnel_set_port+0x135/0x150 drivers/net/netdevsim/udp_tunnels.c:31
 udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline]
 udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:249 [inline]
 __udp_tunnel_nic_device_sync+0x575/0x9b0 net/ipv4/udp_tunnel_nic.c:292
 udp_tunnel_nic_device_sync_work+0x5d/0x580 net/ipv4/udp_tunnel_nic.c:740
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3397
 worker_thread+0x58a/0x780 kernel/workqueue.c:3478
 kthread+0x22a/0x280 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffffffff86c07a00 of 8 bytes by task 29250 on cpu 0:
 mem_cgroup_flush_stats_ratelimited+0x29/0x50 mm/memcontrol.c:743
 count_shadow_nodes+0x6a/0x250 mm/workingset.c:692
 do_shrink_slab+0x63/0x660 mm/shrinker.c:382
 shrink_slab_memcg mm/shrinker.c:553 [inline]
 shrink_slab+0x545/0x8f0 mm/shrinker.c:631
 shrink_node_memcgs mm/vmscan.c:6173 [inline]
 shrink_node+0x6d4/0x20a0 mm/vmscan.c:6215
 shrink_zones mm/vmscan.c:6454 [inline]
 do_try_to_free_pages+0x408/0xc90 mm/vmscan.c:6516
 try_to_free_mem_cgroup_pages+0x201/0x420 mm/vmscan.c:6838
 try_charge_memcg+0x373/0xa10 mm/memcontrol.c:2630
 charge_memcg+0x6d/0x120 mm/memcontrol.c:5024
 mem_cgroup_swapin_charge_folio+0xcc/0x150 mm/memcontrol.c:5110
 __swap_cache_prepare_and_add+0x69/0x4a0 mm/swap_state.c:476
 swap_cache_alloc_folio+0xa2/0x120 mm/swap_state.c:552
 swap_cluster_readahead+0x25f/0x3c0 mm/swap_state.c:726
 swapin_readahead+0xde/0x840 mm/swap_state.c:901
 do_swap_page+0x31e/0x2180 mm/memory.c:4891
 handle_pte_fault mm/memory.c:6430 [inline]
 __handle_mm_fault mm/memory.c:6565 [inline]
 handle_mm_fault+0xb30/0x2e70 mm/memory.c:6734
 do_user_addr_fault+0x3fd/0x1050 arch/x86/mm/fault.c:1385
 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
 __get_user_8+0x14/0x30 arch/x86/lib/getuser.S:100
 fetch_robust_entry kernel/futex/core.c:1138 [inline]
 exit_robust_list+0x31/0x280 kernel/futex/core.c:1166
 futex_cleanup kernel/futex/core.c:1410 [inline]
 futex_exit_release+0xe0/0x130 kernel/futex/core.c:1515
 exit_mm_release+0x1a/0x30 kernel/fork.c:1498
 exit_mm+0x38/0x1f0 kernel/exit.c:554
 do_exit+0x442/0x1530 kernel/exit.c:964
 do_group_exit+0xfe/0x140 kernel/exit.c:1119
 get_signal+0xe30/0xf20 kernel/signal.c:3038
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x6f/0x820 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x232/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000010001609d -> 0x000000010001609e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 29250 Comm: syz.0.6607 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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