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BUG: KCSAN: data-race in lru_add_drain_all / pagevec_lru_move_fn

read to 0xffff88812bf27620 of 1 bytes by task 3067 on cpu 0:
 lru_add_drain_all+0xf5/0x350 mm/swap.c:728
 invalidate_bdev+0x6e/0x90 fs/block_dev.c:97
 btrfs_get_bdev_and_sb+0xbb/0x1a0 fs/btrfs/volumes.c:488
 btrfs_open_one_device fs/btrfs/volumes.c:797 [inline]
 open_fs_devices+0x3d2/0x640 fs/btrfs/volumes.c:1336
 btrfs_open_devices+0xc5/0xd0 fs/btrfs/volumes.c:1381
 btrfs_mount_root+0x4b8/0xb00 fs/btrfs/super.c:1533
 legacy_get_tree+0x7e/0xf0 fs/fs_context.c:647
 vfs_get_tree+0x56/0x1a0 fs/super.c:1545
 fc_mount+0x20/0x80 fs/namespace.c:962
 vfs_kern_mount.part.0+0xe6/0xf0 fs/namespace.c:992
 vfs_kern_mount+0x49/0x70 fs/namespace.c:979
 btrfs_mount+0x250/0xf37 fs/btrfs/super.c:1621
 legacy_get_tree+0x7e/0xf0 fs/fs_context.c:647
 vfs_get_tree+0x56/0x1a0 fs/super.c:1545
 do_new_mount fs/namespace.c:2822 [inline]
 do_mount+0x1004/0x14f0 fs/namespace.c:3142
 ksys_mount+0xe8/0x160 fs/namespace.c:3351
 __do_sys_mount fs/namespace.c:3365 [inline]
 __se_sys_mount fs/namespace.c:3362 [inline]
 __x64_sys_mount+0x70/0x90 fs/namespace.c:3362
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff88812bf27620 of 1 bytes by task 2961 on cpu 1:
 pagevec_reinit include/linux/pagevec.h:63 [inline]
 pagevec_lru_move_fn+0x163/0x180 mm/swap.c:216
 __pagevec_lru_add mm/swap.c:966 [inline]
 lru_add_drain_cpu+0x178/0x2e0 mm/swap.c:594
 lru_add_drain+0x35/0x80 mm/swap.c:689
 __pagevec_release+0x74/0x90 mm/swap.c:859
 pagevec_release include/linux/pagevec.h:88 [inline]
 shmem_undo_range+0x7f3/0x13f0 mm/shmem.c:870
 shmem_truncate_range+0x30/0x80 mm/shmem.c:992
 shmem_evict_inode+0x1b5/0x550 mm/shmem.c:1092
 evict+0x244/0x410 fs/inode.c:574
 iput_final fs/inode.c:1563 [inline]
 iput+0x371/0x4e0 fs/inode.c:1589
 dentry_unlink_inode+0x270/0x2e0 fs/dcache.c:374
 __dentry_kill+0x220/0x3c0 fs/dcache.c:579
 dentry_kill fs/dcache.c:686 [inline]
 dput+0x442/0x750 fs/dcache.c:859
 __fput+0x2ac/0x520 fs/file_table.c:293
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2961 Comm: syz-executor.3 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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