================================================================== 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 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705 get_mem_cgroup_from_mm+0x138/0x190 mm/memcontrol.c:949 __mem_cgroup_charge+0x19/0x150 mm/memcontrol.c:4761 mem_cgroup_charge include/linux/memcontrol.h:665 [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_write_begin+0xfc/0x1f0 mm/shmem.c:3326 generic_perform_write+0x183/0x490 mm/filemap.c:4314 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3501 __kernel_write_iter+0x319/0x590 fs/read_write.c:621 dump_emit_page fs/coredump.c:1299 [inline] dump_user_range+0xa7d/0xdb0 fs/coredump.c:1373 elf_core_dump+0x21a2/0x2330 fs/binfmt_elf.c:2111 coredump_write+0xacf/0xdf0 fs/coredump.c:1050 do_coredump fs/coredump.c:1127 [inline] vfs_coredump+0x26c7/0x3130 fs/coredump.c:1201 get_signal+0xd80/0xf60 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:64 [inline] exit_to_user_mode_loop kernel/entry/common.c:98 [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+0xf7/0x520 kernel/entry/common.c:219 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 read to 0xffffffff86c09a00 of 8 bytes by task 4342 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:6012 [inline] shrink_node+0x6bd/0x20c0 mm/vmscan.c:6051 shrink_zones mm/vmscan.c:6290 [inline] do_try_to_free_pages+0x408/0xc80 mm/vmscan.c:6352 try_to_free_mem_cgroup_pages+0x1f5/0x470 mm/vmscan.c:6673 try_charge_memcg+0x37e/0xa10 mm/memcontrol.c:2414 try_charge mm/memcontrol.c:2556 [inline] charge_memcg mm/memcontrol.c:4745 [inline] __mem_cgroup_charge+0x65/0x150 mm/memcontrol.c:4762 mem_cgroup_charge include/linux/memcontrol.h:665 [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_write_begin+0xfc/0x1f0 mm/shmem.c:3326 generic_perform_write+0x183/0x490 mm/filemap.c:4314 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3501 __kernel_write_iter+0x319/0x590 fs/read_write.c:621 dump_emit_page fs/coredump.c:1299 [inline] dump_user_range+0xa7d/0xdb0 fs/coredump.c:1373 elf_core_dump+0x21a2/0x2330 fs/binfmt_elf.c:2111 coredump_write+0xacf/0xdf0 fs/coredump.c:1050 do_coredump fs/coredump.c:1127 [inline] vfs_coredump+0x26c7/0x3130 fs/coredump.c:1201 get_signal+0xd80/0xf60 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:64 [inline] exit_to_user_mode_loop kernel/entry/common.c:98 [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+0xf7/0x520 kernel/entry/common.c:219 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 value changed: 0x00000000ffffac71 -> 0x00000000ffffac72 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 4342 Comm: syz.0.221 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 ==================================================================