EXT4-fs (loop6): 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 0xffff888237d26528 of 1 bytes by task 13069 on cpu 1:
 folio_batch_add include/linux/folio_batch.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:229 [inline]
 folio_add_lru+0xa4/0x250 mm/swap.c:562
 folio_add_lru_vma+0x49/0x70 mm/swap.c:581
 wp_page_copy mm/memory.c:3943 [inline]
 do_wp_page+0x13a5/0x2030 mm/memory.c:4336
 handle_pte_fault mm/memory.c:6395 [inline]
 __handle_mm_fault mm/memory.c:6517 [inline]
 handle_mm_fault+0x8bc/0x2da0 mm/memory.c:6686
 do_user_addr_fault+0x402/0x1060 arch/x86/mm/fault.c:1394
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
 rep_movs_alternative+0x4a/0xa0 arch/x86/lib/copy_user_64.S:68
 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
 copy_to_user_iter lib/iov_iter.c:25 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0x141/0xea0 lib/iov_iter.c:197
 copy_to_iter include/linux/uio.h:220 [inline]
 simple_copy_to_iter net/core/datagram.c:521 [inline]
 __skb_datagram_iter+0xc6/0x680 net/core/datagram.c:402
 skb_copy_datagram_iter+0x3f/0xf0 net/core/datagram.c:535
 skb_copy_datagram_msg include/linux/skbuff.h:4244 [inline]
 unix_stream_read_actor+0x43/0x70 net/unix/af_unix.c:3121
 unix_stream_read_generic+0x6e9/0x15f0 net/unix/af_unix.c:3041
 unix_stream_recvmsg+0xfc/0x130 net/unix/af_unix.c:3158
 sock_recvmsg_nosec net/socket.c:1126 [inline]
 sock_recvmsg+0xf5/0x120 net/socket.c:1148
 ____sys_recvmsg+0xf5/0x280 net/socket.c:2904
 ___sys_recvmsg+0x11f/0x3a0 net/socket.c:2946
 __sys_recvmsg net/socket.c:2979 [inline]
 __do_sys_recvmsg net/socket.c:2985 [inline]
 __se_sys_recvmsg net/socket.c:2982 [inline]
 __x64_sys_recvmsg+0xd1/0x160 net/socket.c:2982
 x64_sys_call+0x2b1a/0x3020 arch/x86/include/generated/asm/syscalls_64.h:48
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d26528 of 1 bytes by task 8998 on cpu 0:
 folio_batch_count include/linux/folio_batch.h:56 [inline]
 cpu_needs_drain mm/swap.c:831 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:928
 lru_add_drain_all+0x10/0x20 mm/swap.c:944
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x614/0x7c0 fs/ext4/super.c:1355
 generic_shutdown_super+0xee/0x220 fs/super.c:647
 kill_block_super+0x2a/0x70 fs/super.c:1665
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7499
 deactivate_locked_super+0x75/0x1c0 fs/super.c:477
 deactivate_super+0x97/0xa0 fs/super.c:510
 cleanup_mnt+0x2c3/0x340 fs/namespace.c:1317
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1324
 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:70 [inline]
 exit_to_user_mode_loop+0x1e4/0x8c0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x23c/0x3c0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x07 -> 0x0c

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8998 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
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