FAT-fs (loop4): bogus number of reserved sectors
FAT-fs (loop4): Can't find a valid FAT filesystem
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BUG: KCSAN: data-race in __lru_cache_add / lru_add_drain_all

write to 0xffff88812c129c40 of 1 bytes by task 15095 on cpu 1:
 pagevec_add include/linux/pagevec.h:81 [inline]
 __lru_cache_add+0xb8/0x1c0 mm/swap.c:410
 lru_cache_add mm/swap.c:447 [inline]
 lru_cache_add_active_or_unevictable+0xb0/0x1e0 mm/swap.c:477
 wp_page_copy+0x79c/0x1060 mm/memory.c:2717
 do_wp_page+0x224/0xca0 mm/memory.c:2982
 handle_pte_fault mm/memory.c:4231 [inline]
 __handle_mm_fault+0x2a65/0x2ec0 mm/memory.c:4345
 handle_mm_fault+0x21c/0x540 mm/memory.c:4382
 do_user_addr_fault arch/x86/mm/fault.c:1464 [inline]
 do_page_fault+0x48a/0xa96 arch/x86/mm/fault.c:1535
 page_fault+0x34/0x40 arch/x86/entry/entry_64.S:1203

read to 0xffff88812c129c40 of 1 bytes by task 15091 on cpu 0:
 lru_add_drain_all+0x169/0x3a0 mm/swap.c:746
 invalidate_bdev+0x65/0x90 fs/block_dev.c:98
 __loop_clr_fd+0x24e/0x710 drivers/block/loop.c:1162
 loop_clr_fd drivers/block/loop.c:1259 [inline]
 lo_ioctl+0x24a/0xc50 drivers/block/loop.c:1628
 __blkdev_driver_ioctl block/ioctl.c:322 [inline]
 blkdev_ioctl+0x1a1/0x420 block/ioctl.c:718
 block_ioctl+0x91/0xb0 fs/block_dev.c:1996
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x101/0x150 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x47/0x60 fs/ioctl.c:770
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15091 Comm: syz-executor.4 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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