4 files changed, 25 insertions, 3 deletions
diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c
index 934985d14c24..4097987b330e 100644
--- a/drivers/xen/gntalloc.c
+++ b/drivers/xen/gntalloc.c
@@ -535,7 +535,7 @@ static int gntalloc_mmap(struct file *filp, struct vm_area_struct *vma)
 
 	vma->vm_private_data = vm_priv;
 
-	vma->vm_flags |= VM_RESERVED | VM_DONTEXPAND;
+	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 
 	vma->vm_ops = &gntalloc_vmops;
 
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 5df9fd847b2e..610bfc6be177 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -720,7 +720,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
 
 	vma->vm_ops = &gntdev_vmops;
 
-	vma->vm_flags |= VM_RESERVED|VM_DONTEXPAND;
+	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 
 	if (use_ptemod)
 		vma->vm_flags |= VM_DONTCOPY;
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index ef6389580b8c..8adb9cc267f9 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -455,7 +455,8 @@ static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
 {
 	/* DONTCOPY is essential for Xen because copy_page_range doesn't know
 	 * how to recreate these mappings */
-	vma->vm_flags |= VM_RESERVED | VM_IO | VM_DONTCOPY | VM_PFNMAP;
+	vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTCOPY |
+			 VM_DONTEXPAND | VM_DONTDUMP;
 	vma->vm_ops = &privcmd_vm_ops;
 	vma->vm_private_data = NULL;
 
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index 131dec04794e..48220e129f85 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -48,6 +48,7 @@
 #include <xen/xenbus.h>
 #include <xen/xen.h>
 #include "xenbus_comms.h"
+#include <asm/xen/hypervisor.h>
 
 struct xs_stored_msg {
 	struct list_head list;
@@ -618,7 +619,24 @@ static struct xenbus_watch *find_watch(const char *token)
 
 	return NULL;
 }
+/*
+ * Certain older XenBus toolstack cannot handle reading values that are
+ * not populated. Some Xen 3.4 installation are incapable of doing this
+ * so if we are running on anything older than 4 do not attempt to read
+ * control/platform-feature-xs_reset_watches.
+ */
+static bool xen_strict_xenbus_quirk()
+{
+	uint32_t eax, ebx, ecx, edx, base;
+
+	base = xen_cpuid_base();
+	cpuid(base + 1, &eax, &ebx, &ecx, &edx);
 
+	if ((eax >> 16) < 4)
+		return true;
+	return false;
+
+}
 static void xs_reset_watches(void)
 {
 	int err, supported = 0;
@@ -626,6 +644,9 @@ static void xs_reset_watches(void)
 	if (!xen_hvm_domain() || xen_initial_domain())
 		return;
 
+	if (xen_strict_xenbus_quirk())
+		return;
+
 	err = xenbus_scanf(XBT_NIL, "control",
 			"platform-feature-xs_reset_watches", "%d", &supported);
 	if (err != 1 || !supported)