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BUG: KCSAN: data-race in mem_cgroup_flush_stats_ratelimited / tick_do_update_jiffies64

read-write to 0xffffffff86a09a00 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:1777 [inline]
 __hrtimer_run_queues+0x20f/0x590 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1d0 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
 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705
 blk_start_plug_nr_ios block/blk-core.c:1140 [inline]
 blk_start_plug+0x84/0xc0 block/blk-core.c:1175
 lru_gen_shrink_lruvec mm/vmscan.c:5019 [inline]
 shrink_lruvec+0xbd/0x1bc0 mm/vmscan.c:5784
 shrink_node_memcgs mm/vmscan.c:6020 [inline]
 shrink_node+0x68e/0x2000 mm/vmscan.c:6061
 shrink_zones mm/vmscan.c:6300 [inline]
 do_try_to_free_pages+0x404/0xcc0 mm/vmscan.c:6362
 try_to_free_mem_cgroup_pages+0x222/0x470 mm/vmscan.c:6690
 try_charge_memcg+0x37e/0xa10 mm/memcontrol.c:2388
 try_charge mm/memcontrol.c:2530 [inline]
 charge_memcg mm/memcontrol.c:4728 [inline]
 __mem_cgroup_charge+0x65/0x150 mm/memcontrol.c:4745
 mem_cgroup_charge include/linux/memcontrol.h:663 [inline]
 shmem_alloc_and_add_folio mm/shmem.c:1965 [inline]
 shmem_get_folio_gfp+0x47b/0xd60 mm/shmem.c:2579
 shmem_get_folio mm/shmem.c:2685 [inline]
 shmem_write_begin+0xfc/0x1f0 mm/shmem.c:3338
 generic_perform_write+0x183/0x490 mm/filemap.c:4314
 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3513
 __kernel_write_iter+0x319/0x590 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1298 [inline]
 dump_user_range+0xa7d/0xdb0 fs/coredump.c:1372
 elf_core_dump+0x21a2/0x2330 fs/binfmt_elf.c:2111
 coredump_write+0xacf/0xdf0 fs/coredump.c:1049
 do_coredump fs/coredump.c:1126 [inline]
 vfs_coredump+0x26bc/0x3120 fs/coredump.c:1200
 get_signal+0xd7b/0xf60 kernel/signal.c:3019
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
 irqentry_exit+0xf7/0x510 kernel/entry/common.c:196
 exc_general_protection+0x153/0x1e0 arch/x86/kernel/traps.c:913
 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:612

read to 0xffffffff86a09a00 of 8 bytes by task 28032 on cpu 0:
 mem_cgroup_flush_stats_ratelimited+0x29/0x70 mm/memcontrol.c:636
 count_shadow_nodes+0x6a/0x230 mm/workingset.c:678
 do_shrink_slab+0x63/0x670 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+0x6cb/0x2000 mm/vmscan.c:6061
 shrink_zones mm/vmscan.c:6300 [inline]
 do_try_to_free_pages+0x404/0xcc0 mm/vmscan.c:6362
 try_to_free_mem_cgroup_pages+0x222/0x470 mm/vmscan.c:6690
 try_charge_memcg+0x37e/0xa10 mm/memcontrol.c:2388
 try_charge mm/memcontrol.c:2530 [inline]
 charge_memcg mm/memcontrol.c:4728 [inline]
 __mem_cgroup_charge+0x65/0x150 mm/memcontrol.c:4745
 mem_cgroup_charge include/linux/memcontrol.h:663 [inline]
 shmem_alloc_and_add_folio mm/shmem.c:1965 [inline]
 shmem_get_folio_gfp+0x47b/0xd60 mm/shmem.c:2579
 shmem_get_folio mm/shmem.c:2685 [inline]
 shmem_write_begin+0xfc/0x1f0 mm/shmem.c:3338
 generic_perform_write+0x183/0x490 mm/filemap.c:4314
 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3513
 __kernel_write_iter+0x319/0x590 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1298 [inline]
 dump_user_range+0xa7d/0xdb0 fs/coredump.c:1372
 elf_core_dump+0x21a2/0x2330 fs/binfmt_elf.c:2111
 coredump_write+0xacf/0xdf0 fs/coredump.c:1049
 do_coredump fs/coredump.c:1126 [inline]
 vfs_coredump+0x26bc/0x3120 fs/coredump.c:1200
 get_signal+0xd7b/0xf60 kernel/signal.c:3019
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
 irqentry_exit+0xf7/0x510 kernel/entry/common.c:196
 exc_general_protection+0x153/0x1e0 arch/x86/kernel/traps.c:913
 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:612

value changed: 0x000000010000bd73 -> 0x000000010000bd74

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 28032 Comm: syz.5.5738 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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