EXT4-fs (loop8): unmounting filesystem 00000000-0000-0000-0000-000000000000.
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BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237c26668 of 1 bytes by task 15846 on cpu 0:
 folio_batch_add include/linux/pagevec.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xa4/0x1e0 mm/swap.c:511
 folio_add_lru_vma+0x49/0x70 mm/swap.c:530
 set_pte_range+0x235/0x4f0 mm/memory.c:5523
 finish_fault+0x937/0xaf0 mm/memory.c:5663
 do_cow_fault mm/memory.c:5841 [inline]
 do_fault mm/memory.c:5935 [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+0x1dd5/0x3020 mm/memory.c:6624
 do_user_addr_fault+0x3fd/0x1050 arch/x86/mm/fault.c:1385
 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
 rep_stos_alternative+0x40/0x80 arch/x86/lib/clear_page_64.S:72
 __clear_user arch/x86/include/asm/uaccess_64.h:188 [inline]
 clear_user arch/x86/include/asm/uaccess_64.h:205 [inline]
 padzero fs/binfmt_elf.c:134 [inline]
 elf_load+0x3ba/0x500 fs/binfmt_elf.c:436
 load_elf_binary+0xbe6/0x1a20 fs/binfmt_elf.c:1189
 search_binary_handler fs/exec.c:1664 [inline]
 exec_binprm fs/exec.c:1696 [inline]
 bprm_execve+0x476/0x9c0 fs/exec.c:1748
 kernel_execve+0x5ea/0x630 fs/exec.c:1892
 call_usermodehelper_exec_async+0x196/0x250 kernel/umh.c:109
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237c26668 of 1 bytes by task 14437 on cpu 1:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:877
 lru_add_drain_all+0x10/0x20 mm/swap.c:893
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x624/0x7d0 fs/ext4/super.c:1353
 generic_shutdown_super+0xee/0x220 fs/super.c:646
 kill_block_super+0x2a/0x70 fs/super.c:1725
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7459
 deactivate_locked_super+0x75/0x1c0 fs/super.c:476
 deactivate_super+0x97/0xa0 fs/super.c:509
 cleanup_mnt+0x2bb/0x330 fs/namespace.c:1312
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1319
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
 exit_to_user_mode_loop+0x1f4/0x6f0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x03 -> 0x04

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 14437 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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