From 2190c8160a802560029d5d260d5f6979302b53d0 Mon Sep 17 00:00:00 2001
From: Jan Beulich <jbeulich@suse.com>
Date: Thu, 15 Nov 2018 16:43:36 +0100
Subject: [PATCH] x86/shadow: emulate_gva_to_mfn() should respect
 p2m_ioreq_server

Writes to such pages need to be handed to the emulator.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
---
 xen/arch/x86/mm/shadow/hvm.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/xen/arch/x86/mm/shadow/hvm.c b/xen/arch/x86/mm/shadow/hvm.c
index 4cc75916b8..8994cb9f87 100644
--- a/xen/arch/x86/mm/shadow/hvm.c
+++ b/xen/arch/x86/mm/shadow/hvm.c
@@ -338,6 +338,11 @@ static mfn_t emulate_gva_to_mfn(struct vcpu *v, unsigned long vaddr,
     {
         return _mfn(BAD_GFN_TO_MFN);
     }
+    if ( p2mt == p2m_ioreq_server )
+    {
+        put_page(page);
+        return _mfn(BAD_GFN_TO_MFN);
+    }
     if ( p2m_is_discard_write(p2mt) )
     {
         put_page(page);
-- 
2.30.2