EXT4-fs (loop3): unmounting filesystem 76b65be2-f6da-4727-8c75-0525a5b65a09.
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BUG: KCSAN: data-race in __lru_add_drain_all / folios_put_refs

write to 0xffff888237c2a928 of 1 bytes by task 14917 on cpu 0:
 folio_batch_reinit include/linux/pagevec.h:50 [inline]
 folios_put_refs+0x26d/0x2b0 mm/swap.c:988
 folios_put include/linux/mm.h:1548 [inline]
 folio_batch_move_lru+0x202/0x230 mm/swap.c:175
 __folio_batch_add_and_move mm/swap.c:196 [inline]
 folio_add_lru+0x145/0x1f0 mm/swap.c:505
 shmem_alloc_and_add_folio mm/shmem.c:1961 [inline]
 shmem_get_folio_gfp+0x7d6/0xd90 mm/shmem.c:2545
 shmem_get_folio mm/shmem.c:2651 [inline]
 shmem_write_begin+0xa2/0x180 mm/shmem.c:3301
 generic_perform_write+0x1a8/0x4a0 mm/filemap.c:4102
 shmem_file_write_iter+0xc2/0xe0 mm/shmem.c:3477
 __kernel_write_iter+0x247/0x4c0 fs/read_write.c:612
 dump_emit_page fs/coredump.c:885 [inline]
 dump_user_range+0x3ac/0x550 fs/coredump.c:946
 elf_core_dump+0x1d17/0x1ea0 fs/binfmt_elf.c:2129
 do_coredump+0x17fe/0x1f40 fs/coredump.c:759
 get_signal+0xd4f/0x1000 kernel/signal.c:3021
 arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 irqentry_exit_to_user_mode+0xa7/0x120 kernel/entry/common.c:231
 irqentry_exit+0x12/0x50 kernel/entry/common.c:334
 exc_general_protection+0x33d/0x4d0 arch/x86/kernel/traps.c:693
 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:617

read to 0xffff888237c2a928 of 1 bytes by task 10959 on cpu 1:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:773 [inline]
 __lru_add_drain_all+0x136/0x3f0 mm/swap.c:867
 lru_add_drain_all+0x10/0x20 mm/swap.c:883
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x571/0x810 fs/ext4/super.c:1356
 generic_shutdown_super+0xe5/0x220 fs/super.c:642
 kill_block_super+0x2a/0x70 fs/super.c:1710
 ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7368
 deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
 deactivate_super+0x9f/0xb0 fs/super.c:506
 cleanup_mnt+0x268/0x2e0 fs/namespace.c:1413
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1420
 task_work_run+0x13a/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xa8/0x120 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x1f -> 0x03

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10959 Comm: syz-executor Tainted: G        W          6.14.0-rc6-syzkaller-00244-g31d7109a19f6 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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