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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 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: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
 __sanitizer_cov_trace_cmp8+0x0/0x90 kernel/kcov.c:289
 __vm_normal_page mm/memory.c:739 [inline]
 vm_normal_page mm/memory.c:767 [inline]
 copy_present_ptes mm/memory.c:1135 [inline]
 copy_pte_range mm/memory.c:1317 [inline]
 copy_pmd_range mm/memory.c:1405 [inline]
 copy_pud_range mm/memory.c:1442 [inline]
 copy_p4d_range mm/memory.c:1466 [inline]
 copy_page_range+0xc8c/0x3d00 mm/memory.c:1552
 dup_mmap+0x892/0x10c0 mm/mmap.c:1841
 dup_mm kernel/fork.c:1530 [inline]
 copy_mm+0x119/0x370 kernel/fork.c:1582
 copy_process+0xe22/0x20d0 kernel/fork.c:2223
 kernel_clone+0x16b/0x5d0 kernel/fork.c:2654
 __do_sys_clone kernel/fork.c:2795 [inline]
 __se_sys_clone kernel/fork.c:2779 [inline]
 __x64_sys_clone+0x143/0x180 kernel/fork.c:2779
 x64_sys_call+0x1222/0x3020 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86c09a00 of 8 bytes by task 22075 on cpu 0:
 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_charge+0x65/0x150 mm/memcontrol.c:4761
 mem_cgroup_charge include/linux/memcontrol.h:664 [inline]
 shmem_alloc_and_add_folio mm/shmem.c:1982 [inline]
 shmem_get_folio_gfp+0x47b/0xd60 mm/shmem.c:2567
 shmem_get_folio mm/shmem.c:2673 [inline]
 shmem_fallocate+0x628/0x920 mm/shmem.c:3790
 vfs_fallocate+0x3b6/0x450 fs/open.c:340
 ksys_fallocate fs/open.c:364 [inline]
 __do_sys_fallocate fs/open.c:369 [inline]
 __se_sys_fallocate fs/open.c:367 [inline]
 __x64_sys_fallocate+0x7a/0xd0 fs/open.c:367
 x64_sys_call+0x298e/0x3020 arch/x86/include/generated/asm/syscalls_64.h:286
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000100003bf3 -> 0x0000000100003bf4

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 22075 Comm: syz.2.6101 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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