==================================================================
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
 should_watch kernel/kcsan/core.c:280 [inline]
 check_access kernel/kcsan/core.c:752 [inline]
 __tsan_read8+0x117/0x190 kernel/kcsan/core.c:1025
 ns_of_pid include/linux/pid.h:153 [inline]
 task_active_pid_ns kernel/pid.c:570 [inline]
 pid_vnr+0x53/0x100 kernel/pid.c:549
 scm_set_cred include/net/scm.h:73 [inline]
 unix_skb_to_scm net/unix/af_unix.c:1998 [inline]
 __unix_dgram_recvmsg+0x5be/0x870 net/unix/af_unix.c:2624
 unix_dgram_recvmsg+0x81/0x90 net/unix/af_unix.c:2672
 sock_recvmsg_nosec+0xc2/0xf0 net/socket.c:1078
 ____sys_recvmsg+0x26f/0x280 net/socket.c:2810
 ___sys_recvmsg+0x11f/0x3b0 net/socket.c:2854
 do_recvmmsg+0x1ef/0x560 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3039
 x64_sys_call+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300
 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 12120 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
 obj_cgroup_charge_pages+0x23/0xc0 mm/memcontrol.c:2857
 obj_cgroup_charge_account+0x73/0x1a0 mm/memcontrol.c:3160
 __memcg_slab_post_alloc_hook+0x392/0x540 mm/memcontrol.c:3249
 memcg_slab_post_alloc_hook mm/slub.c:2457 [inline]
 slab_post_alloc_hook mm/slub.c:4549 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_noprof+0x1e2/0x400 mm/slub.c:4873
 alloc_buffer_head+0x35/0x1f0 fs/buffer.c:3026
 folio_alloc_buffers+0x149/0x310 fs/buffer.c:932
 create_empty_buffers+0x2c/0x200 fs/buffer.c:1688
 folio_create_buffers fs/buffer.c:1799 [inline]
 __block_write_begin_int+0x1d4/0xf90 fs/buffer.c:2123
 block_page_mkwrite+0x1a8/0x3c0 fs/buffer.c:2636
 ext4_page_mkwrite+0x859/0xb90 fs/ext4/inode.c:6682
 do_page_mkwrite mm/memory.c:3589 [inline]
 do_shared_fault mm/memory.c:5875 [inline]
 do_fault mm/memory.c:5937 [inline]
 do_pte_missing mm/memory.c:4477 [inline]
 handle_pte_fault mm/memory.c:6317 [inline]
 __handle_mm_fault mm/memory.c:6455 [inline]
 handle_mm_fault+0x1904/0x3020 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: 0x0000000100001bbf -> 0x0000000100001bc0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 12120 Comm: syz.0.2820 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================