loop4: detected capacity change from 0 to 264192
EXT4-fs warning (device loop4): read_mmp_block:107: Error -117 while reading MMP block 0
==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / __pagevec_lru_add

write to 0xffff888237c22528 of 1 bytes by task 18437 on cpu 0:
 pagevec_reinit include/linux/pagevec.h:56 [inline]
 __pagevec_lru_add+0x211/0x240 mm/swap.c:1044
 lru_add_drain_cpu+0x6d/0x280 mm/swap.c:597
 lru_add_drain+0x28/0x40 mm/swap.c:702
 exit_mmap+0x218/0x470 mm/mmap.c:3166
 __mmput+0x27/0x1d0 kernel/fork.c:1115
 mmput+0x3d/0x50 kernel/fork.c:1136
 free_bprm+0xce/0x1f0 fs/exec.c:1483
 kernel_execve+0x4e9/0x640 fs/exec.c:1980
 call_usermodehelper_exec_async+0x1d8/0x290 kernel/umh.c:112
 ret_from_fork+0x1f/0x30

read to 0xffff888237c22528 of 1 bytes by task 18423 on cpu 1:
 pagevec_count include/linux/pagevec.h:61 [inline]
 __lru_add_drain_all+0x12c/0x3e0 mm/swap.c:806
 lru_add_drain_all+0xc/0x10 mm/swap.c:828
 invalidate_bdev+0x56/0x80 block/bdev.c:87
 __loop_clr_fd+0x521/0x850 drivers/block/loop.c:1399
 loop_clr_fd drivers/block/loop.c:1494 [inline]
 lo_ioctl+0xac5/0x13e0 drivers/block/loop.c:1850
 blkdev_ioctl+0x1d0/0x3f0 block/ioctl.c:589
 block_ioctl+0x6e/0x80 block/fops.c:477
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18423 Comm: syz-executor.4 Tainted: G        W         5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
loop4: detected capacity change from 0 to 264192
EXT4-fs warning (device loop4): read_mmp_block:107: Error -117 while reading MMP block 0