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BUG: KCSAN: data-race in copy_mm / percpu_counter_destroy_many

write to 0xffff88810d2748c8 of 8 bytes by task 6164 on cpu 0:
 __list_del include/linux/list.h:241 [inline]
 __list_del_entry include/linux/list.h:264 [inline]
 list_del include/linux/list.h:275 [inline]
 percpu_counter_destroy_many+0xbd/0x320 lib/percpu_counter.c:244
 __mmdrop+0x1c9/0x340 kernel/fork.c:741
 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+0x296/0x340 kernel/sched/core.c:5465
 context_switch kernel/sched/core.c:5586 [inline]
 __schedule+0x7a9/0xd40 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x5b/0xa0 kernel/sched/core.c:7474
 schedule_timeout+0x53/0x180 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common+0xee/0x1e0 kernel/sched/completion.c:132
 wait_for_completion_state+0x15/0x40 kernel/sched/completion.c:269
 call_usermodehelper_exec+0x270/0x2c0 kernel/umh.c:439
 call_modprobe kernel/module/kmod.c:104 [inline]
 __request_module+0x283/0x3c0 kernel/module/kmod.c:174
 dev_load+0x61/0xc0 net/core/dev_ioctl.c:668
 dev_ioctl+0x4fe/0x960 net/core/dev_ioctl.c:735
 sock_do_ioctl+0x1aa/0x230 net/socket.c:1342
 sock_ioctl+0x439/0x610 net/socket.c:1449
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x239d/0x2550 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810d274380 of 1664 bytes by task 6173 on cpu 1:
 dup_mm kernel/fork.c:1536 [inline]
 copy_mm+0xd1/0x340 kernel/fork.c:1594
 copy_process+0x10e9/0x2400 kernel/fork.c:2320
 kernel_clone+0x1c0/0x5f0 kernel/fork.c:2790
 __do_sys_clone kernel/fork.c:2932 [inline]
 __se_sys_clone kernel/fork.c:2916 [inline]
 __x64_sys_clone+0x143/0x180 kernel/fork.c:2916
 x64_sys_call+0x2479/0x2550 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6173 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
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