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-rw-r--r--docs/interop/vhost-user.rst20
1 files changed, 20 insertions, 0 deletions
diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst
index edc3ad84a3..4dbc84fd00 100644
--- a/docs/interop/vhost-user.rst
+++ b/docs/interop/vhost-user.rst
@@ -38,6 +38,26 @@ conventions <backend_conventions>`.
 *Master* and *slave* can be either a client (i.e. connecting) or
 server (listening) in the socket communication.
 
+Support for platforms other than Linux
+--------------------------------------
+
+While vhost-user was initially developed targeting Linux, nowadays it
+is supported on any platform that provides the following features:
+
+- A way for requesting shared memory represented by a file descriptor
+  so it can be passed over a UNIX domain socket and then mapped by the
+  other process.
+
+- AF_UNIX sockets with SCM_RIGHTS, so QEMU and the other process can
+  exchange messages through it, including ancillary data when needed.
+
+- Either eventfd or pipe/pipe2. On platforms where eventfd is not
+  available, QEMU will automatically fall back to pipe2 or, as a last
+  resort, pipe. Each file descriptor will be used for receiving or
+  sending events by reading or writing (respectively) an 8-byte value
+  to the corresponding it. The 8-value itself has no meaning and
+  should not be interpreted.
+
 Message Specification
 =====================