FAT-fs (loop3): bogus number of reserved sectors
FAT-fs (loop3): Can't find a valid FAT filesystem
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BUG: KCSAN: data-race in __lru_add_drain_all / __pagevec_lru_add

write to 0xffff888237d264e8 of 1 bytes by task 9219 on cpu 1:
 pagevec_reinit include/linux/pagevec.h:56 [inline]
 __pagevec_lru_add+0x211/0x240 mm/swap.c:1066
 lru_add_drain_cpu+0x6d/0x270 mm/swap.c:619
 lru_add_drain mm/swap.c:724 [inline]
 __pagevec_release+0x57/0xa0 mm/swap.c:989
 pagevec_release include/linux/pagevec.h:81 [inline]
 write_cache_pages+0x6b7/0x810 mm/page-writeback.c:2288
 mpage_writepages+0x6d/0x120 fs/mpage.c:712
 fat_writepages+0x20/0x30 fs/fat/inode.c:205
 do_writepages+0x7b/0x150 mm/page-writeback.c:2355
 __filemap_fdatawrite_range mm/filemap.c:413 [inline]
 filemap_write_and_wait_range+0x20a/0x390 mm/filemap.c:686
 __generic_file_write_iter+0x231/0x300 mm/filemap.c:3775
 generic_file_write_iter+0x75/0x130 mm/filemap.c:3821
 call_write_iter include/linux/fs.h:2114 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888237d264e8 of 1 bytes by task 9270 on cpu 0:
 pagevec_count include/linux/pagevec.h:61 [inline]
 __lru_add_drain_all+0x12c/0x3e0 mm/swap.c:828
 lru_add_drain_all+0xc/0x10 mm/swap.c:850
 invalidate_bdev+0x50/0x70 fs/block_dev.c:96
 __loop_clr_fd+0x52b/0x8b0 drivers/block/loop.c:1336
 loop_clr_fd drivers/block/loop.c:1430 [inline]
 lo_ioctl+0x9f7/0x1210 drivers/block/loop.c:1788
 blkdev_ioctl+0x1d0/0x3c0 block/ioctl.c:585
 block_ioctl+0x6d/0x80 fs/block_dev.c:1602
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:1055
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9270 Comm: syz-executor.3 Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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