[quelsolaar]

Id love a way for userspace applications to leverage the MMUs memory protection to trigger user code. Let me give you an example: Lets say I have large block of memory that is encrypted. I want to random access this memory, but i don't want to decrypt the entire memory before i start using it. I may have worker threads that start decrypting the data for me, but i don't want to wait for them. Ideally, id like to set a memory protection flag on all pages that are still encrypted, and then if any access is made of these pages, a callback will trigger that lets you decrypt the block and remove the flag from the page, only when accessed.

This could be used for things like user space memory mapping of networked memory, where memory is retrieved from a remote computer when accessed. This would make it possible to transparently implement userspace large scale shared memory systems in a very elegant way. Good luck with what ever you decide to do!

[planede]

You could probably do this in userspace now with userfaultfd.

[toast0]

Can't you catch sigsegv since forever?