FAT-fs (loop5): Can't find a valid FAT filesystem
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BUG: KCSAN: data-race in lru_add_drain_all / pagevec_lru_move_fn

write to 0xffff88812c028ac0 of 1 bytes by task 8145 on cpu 0:
 pagevec_reinit include/linux/pagevec.h:63 [inline]
 pagevec_lru_move_fn+0x175/0x190 mm/swap.c:232
 __pagevec_lru_add mm/swap.c:1031 [inline]
 lru_add_drain_cpu+0x75/0x2e0 mm/swap.c:632
 lru_add_drain mm/swap.c:736 [inline]
 __pagevec_release+0x4b/0xc0 mm/swap.c:930
 pagevec_release include/linux/pagevec.h:88 [inline]
 mpage_prepare_extent_to_map+0x5f0/0x650 fs/ext4/inode.c:2619
 ext4_writepages+0x682/0x1ef0 fs/ext4/inode.c:2735
 do_writepages+0x7b/0x150 mm/page-writeback.c:2352
 __filemap_fdatawrite_range+0x19b/0x1d0 mm/filemap.c:422
 file_write_and_wait_range+0x9f/0x120 mm/filemap.c:761
 ext4_sync_file+0xfc/0x6e0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2747 [inline]
 ext4_buffered_write_iter+0x369/0x3b0 fs/ext4/file.c:276
 ext4_file_write_iter+0x768/0x1060 include/linux/fs.h:784
 call_write_iter include/linux/fs.h:1882 [inline]
 do_iter_readv_writev+0x32e/0x3d0 fs/read_write.c:713
 do_iter_write+0x112/0x4b0 fs/read_write.c:1018
 vfs_iter_write+0x4c/0x70 fs/read_write.c:1059
 iter_file_splice_write+0x41a/0x770 fs/splice.c:750
 do_splice_from fs/splice.c:846 [inline]
 direct_splice_actor+0x95/0x160 fs/splice.c:1016
 splice_direct_to_actor+0x365/0x660 fs/splice.c:971
 do_splice_direct+0xf2/0x170 fs/splice.c:1059
 do_sendfile+0x56a/0xba0 fs/read_write.c:1540
 __do_sys_sendfile64 fs/read_write.c:1601 [inline]
 __se_sys_sendfile64 fs/read_write.c:1587 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1587
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812c028ac0 of 1 bytes by task 8154 on cpu 1:
 pagevec_count include/linux/pagevec.h:68 [inline]
 lru_add_drain_all+0x118/0x3b0 mm/swap.c:796
 invalidate_bdev+0x50/0x70 fs/block_dev.c:96
 __loop_clr_fd+0x258/0x5b0 drivers/block/loop.c:1248
 loop_clr_fd drivers/block/loop.c:1345 [inline]
 lo_ioctl+0x9d1/0x1190 drivers/block/loop.c:1703
 __blkdev_driver_ioctl block/ioctl.c:224 [inline]
 blkdev_ioctl+0x1cf/0x410 block/ioctl.c:620
 block_ioctl+0x6d/0x80 fs/block_dev.c:1871
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8154 Comm: syz-executor.5 Not tainted 5.9.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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