BTRFS info (device loop3): using crc32c (crc32c-intel) checksum algorithm
BTRFS info (device loop3): using free space tree
BTRFS info (device loop3): enabling ssd optimizations
BTRFS info (device loop3): auto enabling async discard
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WARNING: lock held when returning to user space!
syzkaller #0 Not tainted
------------------------------------------------
syz.3.577/7966 is leaving the kernel with locks still held!
1 lock held by syz.3.577/7966:
 #0: ffff88814132b360 (&lo->lo_mutex){+.+.}-{3:3}, at: loop_set_block_size+0x7c/0x480 drivers/block/loop.c:1490