On Thu, Oct 17, 2024 at 10:58:29AM -0400, Peter Xu wrote:
My question was more torwards whether gmemfd could still expose the possibility to be used in VA forms to other modules that may not support fd+offsets yet.
I keep hearing they don't want to support page pinning on a guestmemfd mapping, so VA based paths could not work.
I think as long as we can provide gmemfd VMAs like what this series provides, it sounds possible to reuse the old VA interfaces before the CoCo interfaces are ready, so that people can already start leveraging gmemfd backing pages.
And you definitely can't get the private pages out of the VA interface because all the VMA PTEs of private pages are non-present by definition.
Hence, you must use the FD for a lot of use cases here.
Jason