==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / folio_activate

read-write to 0xffff888237c29ac8 of 1 bytes by task 3083 on cpu 0:
 folio_batch_add include/linux/pagevec.h:126 [inline]
 folio_batch_add_and_move mm/swap.c:231 [inline]
 folio_activate+0xbb/0x1c0 mm/swap.c:361
 folio_mark_accessed+0x114/0x190 mm/swap.c:481
 shmem_file_read_iter+0x2e8/0x560 mm/shmem.c:2691
 do_iter_read+0x4b1/0x760 fs/read_write.c:795
 vfs_iter_read+0x50/0x70 fs/read_write.c:837
 lo_read_simple drivers/block/loop.c:290 [inline]
 do_req_filebacked drivers/block/loop.c:500 [inline]
 loop_handle_cmd drivers/block/loop.c:1888 [inline]
 loop_process_work+0x9ac/0x1300 drivers/block/loop.c:1923
 loop_workfn+0x31/0x40 drivers/block/loop.c:1947
 process_one_work+0x3e6/0x750 kernel/workqueue.c:2405
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2552
 kthread+0x1d7/0x210 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

read to 0xffff888237c29ac8 of 1 bytes by task 18137 on cpu 1:
 folio_batch_count include/linux/pagevec.h:105 [inline]
 cpu_needs_drain mm/swap.c:800 [inline]
 __lru_add_drain_all+0x21d/0x420 mm/swap.c:889
 lru_add_drain_all+0x10/0x20 mm/swap.c:905
 invalidate_bdev+0x5a/0x80 block/bdev.c:86
 reconfigure_super+0x3b8/0x540 fs/super.c:981
 do_remount fs/namespace.c:2701 [inline]
 path_mount+0xa2a/0xb40 fs/namespace.c:3361
 do_mount fs/namespace.c:3382 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18137 Comm: syz-executor.3 Not tainted 6.4.0-rc7-syzkaller-00041-ge660abd551f1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
==================================================================