From: Peter Dinda <pdinda@northwestern.edu>
Date: Sun, 2 Aug 2015 23:15:28 +0000 (-0500)
Subject: Have unregistered hypercalls fail to guest
X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?p=palacios.git;a=commitdiff_plain;h=4d1d8fadad33de7d3ebce2083d9782048f78b44e

Have unregistered hypercalls fail to guest
---

diff --git a/palacios/include/palacios/vmm_hypercall.h b/palacios/include/palacios/vmm_hypercall.h
index 9b16618..58c73f9 100644
--- a/palacios/include/palacios/vmm_hypercall.h
+++ b/palacios/include/palacios/vmm_hypercall.h
@@ -56,7 +56,7 @@ typedef enum {
 
     VNET_HEADER_QUERY_HCALL  =   0xe000,        // Get the current header for a src/dest pair
 
-    HVM_HCALL = 0xf000, 
+    HVM_HCALL = 0xf00d, 
 } hcall_id_t;
 
 
diff --git a/palacios/src/palacios/vmm_hypercall.c b/palacios/src/palacios/vmm_hypercall.c
index 59e6484..21e6e96 100644
--- a/palacios/src/palacios/vmm_hypercall.c
+++ b/palacios/src/palacios/vmm_hypercall.c
@@ -181,9 +181,10 @@ int v3_handle_hypercall(struct guest_info * info) {
     struct hypercall * hcall = get_hypercall(info->vm_info, hypercall_id);
 
     if (!hcall) {
-        PrintError(info->vm_info, info,  "Invalid Hypercall (%d(0x%x) not registered)\n", 
+        PrintError(info->vm_info, info,  "Invalid Hypercall (%d(0x%x) not registered) => ignored with rax=-1\n", 
 		   hypercall_id, hypercall_id);
-	return -1;
+	info->vm_regs.rax=-1;
+	return 0;
     }
 
     if (hcall->hcall_fn(info, hypercall_id, hcall->priv_data) != 0) {