From: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Date: Thu, 16 Feb 2012 15:43:02 +0000 (+0000)
Subject: x86/mm: Check sharing/paging/access have been enabled before processing a memop
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=248566396985b2171aae12469c210a46e3709548;p=people%2Fvhanquez%2Fxen.git

x86/mm: Check sharing/paging/access have been enabled before processing a memop

Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Tim Deegan <tim@xen.org>
Committed-by: Tim Deegan <tim@xen.org>
---

diff --git a/xen/arch/x86/mm/mem_access.c b/xen/arch/x86/mm/mem_access.c
index 94a4c30f0..a08416c40 100644
--- a/xen/arch/x86/mm/mem_access.c
+++ b/xen/arch/x86/mm/mem_access.c
@@ -29,6 +29,9 @@ int mem_access_memop(struct domain *d, xen_mem_event_op_t *meo)
 {
     int rc;
 
+    if ( unlikely(!d->mem_event->access.ring_page) )
+        return -ENODEV;
+
     switch( meo->op )
     {
     case XENMEM_access_op_resume:
diff --git a/xen/arch/x86/mm/mem_event.c b/xen/arch/x86/mm/mem_event.c
index 138fcdfdf..3b2267adf 100644
--- a/xen/arch/x86/mm/mem_event.c
+++ b/xen/arch/x86/mm/mem_event.c
@@ -452,13 +452,15 @@ int mem_event_claim_slot(struct domain *d, struct mem_event_domain *med)
 /* Registered with Xen-bound event channel for incoming notifications. */
 static void mem_paging_notification(struct vcpu *v, unsigned int port)
 {
-    p2m_mem_paging_resume(v->domain);
+    if ( likely(v->domain->mem_event->paging.ring_page != NULL) )
+        p2m_mem_paging_resume(v->domain);
 }
 
 /* Registered with Xen-bound event channel for incoming notifications. */
 static void mem_access_notification(struct vcpu *v, unsigned int port)
 {
-    p2m_mem_access_resume(v->domain);
+    if ( likely(v->domain->mem_event->access.ring_page != NULL) )
+        p2m_mem_access_resume(v->domain);
 }
 
 struct domain *get_mem_event_op_target(uint32_t domain, int *rc)
diff --git a/xen/arch/x86/mm/mem_paging.c b/xen/arch/x86/mm/mem_paging.c
index 4fdf3d74b..6cf9b385b 100644
--- a/xen/arch/x86/mm/mem_paging.c
+++ b/xen/arch/x86/mm/mem_paging.c
@@ -27,6 +27,9 @@
 
 int mem_paging_memop(struct domain *d, xen_mem_event_op_t *mec)
 {
+    if ( unlikely(!d->mem_event->paging.ring_page) )
+        return -ENODEV;
+
     switch( mec->op )
     {
     case XENMEM_paging_op_nominate:
diff --git a/xen/arch/x86/mm/mem_sharing.c b/xen/arch/x86/mm/mem_sharing.c
index 36a50e58d..b73d48827 100644
--- a/xen/arch/x86/mm/mem_sharing.c
+++ b/xen/arch/x86/mm/mem_sharing.c
@@ -1022,7 +1022,7 @@ int mem_sharing_memop(struct domain *d, xen_mem_sharing_op_t *mec)
     int rc = 0;
 
     /* Only HAP is supported */
-    if ( !hap_enabled(d) )
+    if ( !hap_enabled(d) || !d->arch.hvm_domain.mem_sharing_enabled )
          return -ENODEV;
 
     switch(mec->op)