On Mon, 9 Dec 2024 22:14:37 +0800 Jijie Shao wrote:

Another way is seq_file, which may be a solution,
as far as I know, each seq_file has a separate buffer and can be expanded automatically.
So it might be possible to solve the problem
But even if the solution is feasible, this will require a major refactoring of hns3 debugfs

seq_file is generally used for text output

can you not hook in the allocation and execution of the cmd into the
.open handler and freeing in to the .close handler? You already use
explicit file_ops for this file.