On Wed, Jun 05, 2019 at 01:14:04PM -0700, Andy Lutomirski wrote:

quoted

On Jun 5, 2019, at 8:17 AM, Jarkko Sakkinen [off-list ref] wrote:

quoted

On Tue, Jun 04, 2019 at 10:10:22PM +0000, Xing, Cedric wrote:
A bit off topic here. This mmap()/mprotect() discussion reminds me a
question (guess for Jarkko): Now that vma->vm_file->private_data keeps
a pointer to the enclave, why do we store it again in vma->vm_private?
It isn't a big deal but non-NULL vm_private does prevent mprotect()
from merging adjacent VMAs. 

Same semantics as with a regular mmap i.e. you can close the file and
still use the mapping.

The file should be properly refcounted — vm_file should not go away while it’s mapped.

Right, makes sense. It is easy one to change essentially just removing
internal refcount from sgx_encl and using file for the same. I'll update
this to my tree along with the changes to remove LKM/ACPI bits ASAP.

/Jarkko