Merge tag 'char-misc-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char and misc and other tiny driver subsystem
  updates for 5.16-rc1.

  Loads of things in here, all of which have been in linux-next for a
  while with no reported problems (except for one called out below.)

  Included are:

   - habanana labs driver updates, including dma_buf usage, reviewed and
     acked by the dma_buf maintainers

   - iio driver update (going through this tree not staging as they
     really do not belong going through that tree anymore)

   - counter driver updates

   - hwmon driver updates that the counter drivers needed, acked by the
     hwmon maintainer

   - xillybus driver updates

   - binder driver updates

   - extcon driver updates

   - dma_buf module namespaces added (will cause a build error in arm64
     for allmodconfig, but that change is on its way through the drm
     tree)

   - lkdtm driver updates

   - pvpanic driver updates

   - phy driver updates

   - virt acrn and nitr_enclaves driver updates

   - smaller char and misc driver updates"

* tag 'char-misc-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (386 commits)
  comedi: dt9812: fix DMA buffers on stack
  comedi: ni_usb6501: fix NULL-deref in command paths
  arm64: errata: Enable TRBE workaround for write to out-of-range address
  arm64: errata: Enable workaround for TRBE overwrite in FILL mode
  coresight: trbe: Work around write to out of range
  coresight: trbe: Make sure we have enough space
  coresight: trbe: Add a helper to determine the minimum buffer size
  coresight: trbe: Workaround TRBE errata overwrite in FILL mode
  coresight: trbe: Add infrastructure for Errata handling
  coresight: trbe: Allow driver to choose a different alignment
  coresight: trbe: Decouple buffer base from the hardware base
  coresight: trbe: Add a helper to pad a given buffer area
  coresight: trbe: Add a helper to calculate the trace generated
  coresight: trbe: Defer the probe on offline CPUs
  coresight: trbe: Fix incorrect access of the sink specific data
  coresight: etm4x: Add ETM PID for Kryo-5XX
  coresight: trbe: Prohibit trace before disabling TRBE
  coresight: trbe: End the AUX handle on truncation
  coresight: trbe: Do not truncate buffer on IRQ
  coresight: trbe: Fix handling of spurious interrupts
  ...

1 files changed, 13 insertions, 8 deletions

diff --git a/Documentation/virt/ne_overview.rst b/Documentation/virt/ne_overview.rst
index 39b0c8fe2654..74c2f5919c88 100644
--- a/Documentation/virt/ne_overview.rst
+++ b/Documentation/virt/ne_overview.rst
@@ -14,12 +14,15 @@ instances [1].
 For example, an application that processes sensitive data and runs in a VM,
 can be separated from other applications running in the same VM. This
 application then runs in a separate VM than the primary VM, namely an enclave.
+It runs alongside the VM that spawned it. This setup matches low latency
+applications needs.
 
-An enclave runs alongside the VM that spawned it. This setup matches low latency
-applications needs. The resources that are allocated for the enclave, such as
-memory and CPUs, are carved out of the primary VM. Each enclave is mapped to a
-process running in the primary VM, that communicates with the NE driver via an
-ioctl interface.
+The current supported architectures for the NE kernel driver, available in the
+upstream Linux kernel, are x86 and ARM64.
+
+The resources that are allocated for the enclave, such as memory and CPUs, are
+carved out of the primary VM. Each enclave is mapped to a process running in the
+primary VM, that communicates with the NE kernel driver via an ioctl interface.
 
 In this sense, there are two components:
 
@@ -43,8 +46,8 @@ for the enclave VM. An enclave does not have persistent storage attached.
 The memory regions carved out of the primary VM and given to an enclave need to
 be aligned 2 MiB / 1 GiB physically contiguous memory regions (or multiple of
 this size e.g. 8 MiB). The memory can be allocated e.g. by using hugetlbfs from
-user space [2][3]. The memory size for an enclave needs to be at least 64 MiB.
-The enclave memory and CPUs need to be from the same NUMA node.
+user space [2][3][7]. The memory size for an enclave needs to be at least
+64 MiB. The enclave memory and CPUs need to be from the same NUMA node.
 
 An enclave runs on dedicated cores. CPU 0 and its CPU siblings need to remain
 available for the primary VM. A CPU pool has to be set for NE purposes by an
@@ -61,7 +64,7 @@ device is placed in memory below the typical 4 GiB.
 The application that runs in the enclave needs to be packaged in an enclave
 image together with the OS ( e.g. kernel, ramdisk, init ) that will run in the
 enclave VM. The enclave VM has its own kernel and follows the standard Linux
-boot protocol [6].
+boot protocol [6][8].
 
 The kernel bzImage, the kernel command line, the ramdisk(s) are part of the
 Enclave Image Format (EIF); plus an EIF header including metadata such as magic
@@ -93,3 +96,5 @@ enclave process can exit.
 [4] https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
 [5] https://man7.org/linux/man-pages/man7/vsock.7.html
 [6] https://www.kernel.org/doc/html/latest/x86/boot.html
+[7] https://www.kernel.org/doc/html/latest/arm64/hugetlbpage.html
+[8] https://www.kernel.org/doc/html/latest/arm64/booting.html