[RFC PATCH 0/2] Drivers: hv: decrypt netvsc buffers on contiguous direct-map addresses

[Kameron Carr <kameroncarr@linux.microsoft.com>]

Some confidential computing implementations only accept linear-map
addresses in set_memory_decrypted(); for example, Arm CCA Realms reject
vmalloc()/vmap() addresses. netvsc currently allocates its large
send/receive buffers via vzalloc() and relies on vmbus_establish_gpadl()
to decrypt them, which fails on those implementations.

This fix allocates the buffers as a list of physically-contiguous chunks,
decrypts each chunk on its direct-map address, and vmap() them together.
Here netvsc fully owns the encryption lifecycle and the vmbus layer must
not call set_memory_decrypted() on establish or set_memory_encrypted() on
teardown.

Kameron Carr (2):
  Drivers: hv: vmbus: add vmbus_establish_gpadl_caller_decrypted()
  hv_netvsc: back GPADL buffers with kmalloc + decrypt + vmap

 drivers/hv/channel.c            | 123 ++++++++++-----
 drivers/net/hyperv/hyperv_net.h |  18 ++-
 drivers/net/hyperv/netvsc.c     | 271 ++++++++++++++++++++++++++++----
 drivers/net/hyperv/netvsc_drv.c |   6 +
 include/linux/hyperv.h          |  11 ++
 5 files changed, 354 insertions(+), 75 deletions(-)


base-commit: a4ffc59238be84dd1c26bf1c001543e832674fc6
-- 
2.45.4