EXT4-fs (loop4): re-mounted 00000000-0000-0000-0000-000000000000 ro.
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BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237c25e68 of 1 bytes by task 3818 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+0xa5/0x1f0 mm/swap.c:505
 filemap_add_folio+0x129/0x1b0 mm/filemap.c:985
 __filemap_get_folio+0x31e/0x650 mm/filemap.c:1979
 ext4_da_write_begin+0x33d/0x670 fs/ext4/inode.c:3074
 generic_perform_write+0x184/0x490 mm/filemap.c:4103
 ext4_buffered_write_iter+0x1ee/0x3c0 fs/ext4/file.c:299
 ext4_file_write_iter+0x383/0xf00 fs/ext4/file.c:-1
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x4a0/0x8e0 fs/read_write.c:686
 ksys_pwrite64 fs/read_write.c:793 [inline]
 __do_sys_pwrite64 fs/read_write.c:801 [inline]
 __se_sys_pwrite64 fs/read_write.c:798 [inline]
 __x64_sys_pwrite64+0xfd/0x150 fs/read_write.c:798
 x64_sys_call+0xe45/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:19
 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 0xffff888237c25e68 of 1 bytes by task 3834 on cpu 1:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:773 [inline]
 __lru_add_drain_all+0x12b/0x3f0 mm/swap.c:867
 lru_add_drain_all+0x10/0x20 mm/swap.c:883
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 reconfigure_super+0x417/0x580 fs/super.c:1098
 do_remount fs/namespace.c:3351 [inline]
 path_mount+0xa86/0xb20 fs/namespace.c:4172
 do_mount fs/namespace.c:4193 [inline]
 __do_sys_mount fs/namespace.c:4404 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4381
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4381
 x64_sys_call+0xd36/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:166
 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

value changed: 0x1a -> 0x1c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3834 Comm: syz.4.101 Not tainted 6.15.0-syzkaller-10815-gbb1556ec9464 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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