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BUG: KCSAN: data-race in copy_mm / percpu_counter_destroy_many

write to 0xffff88810ece7170 of 8 bytes by task 8425 on cpu 1:
 __list_del include/linux/list.h:203 [inline]
 __list_del_entry include/linux/list.h:226 [inline]
 list_del include/linux/list.h:237 [inline]
 percpu_counter_destroy_many+0xc7/0x2b0 lib/percpu_counter.c:244
 __mmdrop+0x22d/0x3c0 kernel/fork.c:691
 mmdrop include/linux/sched/mm.h:55 [inline]
 mmdrop_sched include/linux/sched/mm.h:83 [inline]
 mmdrop_lazy_tlb_sched include/linux/sched/mm.h:110 [inline]
 finish_task_switch+0x187/0x2b0 kernel/sched/core.c:5218
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x6b9/0xb30 kernel/sched/core.c:6929
 preempt_schedule_common kernel/sched/core.c:7113 [inline]
 __cond_resched+0x4e/0x90 kernel/sched/core.c:7458
 might_resched include/linux/kernel.h:61 [inline]
 down_read+0x13/0xe0 kernel/locking/rwsem.c:1536
 kernfs_iop_permission+0x87/0x220 fs/kernfs/inode.c:289
 do_inode_permission fs/namei.c:526 [inline]
 inode_permission+0x1ca/0x310 fs/namei.c:593
 may_lookup fs/namei.c:1873 [inline]
 link_path_walk+0x63c/0x900 fs/namei.c:2467
 path_openat+0x1de/0x2170 fs/namei.c:4130
 do_filp_open+0x109/0x230 fs/namei.c:4161
 do_sys_openat2+0xa6/0x110 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_openat fs/open.c:1466 [inline]
 __se_sys_openat fs/open.c:1461 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1461
 x64_sys_call+0x2eab/0x3000 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810ece6d40 of 1408 bytes by task 10495 on cpu 0:
 dup_mm kernel/fork.c:1483 [inline]
 copy_mm+0xe2/0x370 kernel/fork.c:1541
 copy_process+0xd08/0x2000 kernel/fork.c:2181
 kernel_clone+0x16c/0x5c0 kernel/fork.c:2609
 __do_sys_clone kernel/fork.c:2750 [inline]
 __se_sys_clone kernel/fork.c:2734 [inline]
 __x64_sys_clone+0xe6/0x120 kernel/fork.c:2734
 x64_sys_call+0x119c/0x3000 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10495 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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