hyperv: Add support to process syndbg commands
SynDbg commands can come from two different flows:
1. Hypercalls, in this mode the data being sent is fully
encapsulated network packets.
2. SynDbg specific MSRs, in this mode only the data that needs to be
transfered is passed.
Signed-off-by: Jon Doron <arilou@gmail.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220216102500.692781-4-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/docs/hyperv.txt b/docs/hyperv.txt
index 0417c18..33588a0 100644
--- a/docs/hyperv.txt
+++ b/docs/hyperv.txt
@@ -225,6 +225,21 @@
Note: hv-version-id-* are not enlightenments and thus don't enable Hyper-V
identification when specified without any other enlightenments.
+3.21. hv-syndbg
+===============
+Enables Hyper-V synthetic debugger interface, this is a special interface used
+by Windows Kernel debugger to send the packets through, rather than sending
+them via serial/network .
+When enabled, this enlightenment provides additional communication facilities
+to the guest: SynDbg messages.
+This new communication is used by Windows Kernel debugger rather than sending
+packets via serial/network, adding significant performance boost over the other
+comm channels.
+This enlightenment requires a VMBus device (-device vmbus-bridge,irq=15)
+and the follow enlightenments to work:
+hv-relaxed,hv_time,hv-vapic,hv-vpindex,hv-synic,hv-runtime,hv-stimer
+
+
4. Supplementary features
=========================
