Re: [PATCH 7/9] Pmalloc Rare Write: modify selected pools

[Matthew Wilcox]

On Mon, Apr 23, 2018 at 04:54:56PM +0400, Igor Stoppa wrote:
> While the vanilla version of pmalloc provides support for permanently
> transitioning between writable and read-only of a memory pool, this
> patch seeks to support a separate class of data, which would still
> benefit from write protection, most of the time, but it still needs to
> be modifiable. Maybe very seldom, but still cannot be permanently marked
> as read-only.

This seems like a horrible idea that basically makes this feature useless.
I would say the right way to do this is to have:

struct modifiable_data {
	struct immutable_data *d;
	...
};

Then allocate a new pool, change d and destroy the old pool.