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BUG: KCSAN: data-race in __htab_map_lookup_elem / bpf_lru_pop_free

write to 0xffff88811ac8fc28 of 4 bytes by task 27706 on cpu 0:
 __local_list_add_pending kernel/bpf/bpf_lru_list.c:358 [inline]
 bpf_common_lru_pop_free kernel/bpf/bpf_lru_list.c:457 [inline]
 bpf_lru_pop_free+0xbf0/0xcd0 kernel/bpf/bpf_lru_list.c:504
 prealloc_lru_pop kernel/bpf/hashtab.c:303 [inline]
 __htab_lru_percpu_map_update_elem+0xea/0x600 kernel/bpf/hashtab.c:1349
 bpf_percpu_hash_update+0x61/0xa0 kernel/bpf/hashtab.c:2408
 bpf_map_update_value+0x297/0x3a0 kernel/bpf/syscall.c:266
 generic_map_update_batch+0x3f5/0x540 kernel/bpf/syscall.c:1982
 bpf_map_do_batch+0x258/0x380 kernel/bpf/syscall.c:5344
 __sys_bpf+0x2e0/0x790 kernel/bpf/syscall.c:-1
 __do_sys_bpf kernel/bpf/syscall.c:5943 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:5941
 x64_sys_call+0x2478/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:322
 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 0xffff88811ac8fc28 of 4 bytes by task 21589 on cpu 1:
 lookup_nulls_elem_raw kernel/bpf/hashtab.c:643 [inline]
 __htab_map_lookup_elem+0xab/0x150 kernel/bpf/hashtab.c:673
 htab_lru_percpu_map_lookup_elem+0x20/0xb0 kernel/bpf/hashtab.c:2342
 bpf_prog_1592a6279ab44e8a+0x48/0x50
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2299
 __do_trace_kfree include/trace/events/kmem.h:94 [inline]
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x27b/0x320 mm/slub.c:4829
 pde_free fs/proc/generic.c:42 [inline]
 pde_put+0xd6/0x120 fs/proc/generic.c:688
 remove_proc_subtree+0x2bb/0x3b0 fs/proc/generic.c:782
 ext4_unregister_sysfs+0x5f/0x80 fs/ext4/sysfs.c:604
 ext4_put_super+0x4c/0x7d0 fs/ext4/super.c:1283
 generic_shutdown_super+0xe6/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1755
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7391
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1417
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1424
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x402bf290 -> 0xfd964a78

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 21589 Comm: syz-executor Not tainted 6.16.0-rc7-syzkaller-00034-g25fae0b93d1d #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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EXT4-fs (loop3): unmounting filesystem 00000000-0000-0000-0000-000000000000.