Re: [PATCH RFC] mm: add MAP_EXCLUSIVE to create exclusive user mappings

On Tue, 29 Oct 2019, Mike Rapoport wrote:

I've talked with Thomas yesterday and he suggested something similar:

When the MAP_EXCLUSIVE request comes for the first time, we allocate a huge
page for it and then use this page as a pool of 4K pages for subsequent
requests. Once this huge page is full we allocate a new one and append it
to the pool. When all the 4K pages that comprise the huge page are freed
the huge page is collapsed.

Or write a device driver that allows you to mmap a secure area and avoid
all core kernel modifications?

/dev/securemem or so?

It may exist already.