On Mon, Nov 23, 2020 at 07:28:22AM -0800, Andy Lutomirski wrote:
On Mon, Nov 23, 2020 at 1:54 AM Mike Rapoport <rppt(a)kernel.org>
> From: Mike Rapoport <rppt(a)linux.ibm.com>
> This is an implementation of "secret" mappings backed by a file
> The file descriptor backing secret memory mappings is created using a
> dedicated memfd_secret system call The desired protection mode for the
> memory is configured using flags parameter of the system call. The mmap()
> of the file descriptor created with memfd_secret() will create a "secret"
> memory mapping. The pages in that mapping will be marked as not present in
> the direct map and will have desired protection bits set in the user page
> table. For instance, current implementation allows uncached mappings.
I'm still not ready to ACK uncached mappings on x86. I'm fine with
the concept of allowing privileged users to create UC memory on x86
for testing and experimentation, but it's a big can of worms in
Ok, let's move forward without UC.