Jul 15 15:16:39 acer kernel: fs_may_mount: device 1 busy=0
Jul 15 15:16:39 acer kernel: fs_may_umount: after shrink d_count=1
Jul 15 15:16:39 acer kernel: iput: open count wrapped dev=0 inode=8
count=-1
Jul 15 15:16:39 acer kernel: fs_may_mount: device 775 busy=0
Jul 15 15:16:39 acer kernel: fs_may_mount: device 1 busy=0
Jul 15 15:16:39 acer kernel: iput: open count wrapped dev=0 inode=13
count=-1
Jul 15 15:16:39 acer kernel: iput: open count wrapped dev=0 inode=24
count=-1
Jul 15 15:16:39 acer kernel: iput: open count wrapped dev=0 inode=25
count=-1
Jul 15 15:16:39 acer kernel: iput: open count wrapped dev=0 inode=26
count=-1
Could these be pipe inodes being freed? I noticed you changed the pipe
open to use d_alloc_root. Pipe inodes are created with use count 1.
Mounting and unmounting seems to be working OK.
Will keep testing ...
-Bill