diff -r 36bd4630ad99 tools/libxc/xc_private.c
--- a/tools/libxc/xc_private.c	Wed Aug 18 10:22:48 2010 +0200
+++ b/tools/libxc/xc_private.c	Wed Aug 18 16:39:11 2010 +0200
@@ -175,7 +175,7 @@ void xc_report_progress_step(xc_interfac
 #ifdef __sun__
 
 int lock_pages(void *addr, size_t len) { return 0; }
-void unlock_pages(void *addr, size_t len) { }
+int unlock_pages(void *addr, size_t len) { return 0; }
 
 int hcall_buf_prep(void **addr, size_t len) { return 0; }
 void hcall_buf_release(void **addr, size_t len) { }
@@ -184,20 +184,21 @@ void hcall_buf_release(void **addr, size
 
 int lock_pages(void *addr, size_t len)
 {
-      int e;
+      int e = 0;
       void *laddr = (void *)((unsigned long)addr & PAGE_MASK);
       size_t llen = (len + ((unsigned long)addr - (unsigned long)laddr) +
                      PAGE_SIZE - 1) & PAGE_MASK;
-      e = mlock(laddr, llen);
+      if (mlock(laddr, llen) == -1)
+          e = errno;
       return e;
 }
 
-void unlock_pages(void *addr, size_t len)
+int unlock_pages(void *addr, size_t len)
 {
     void *laddr = (void *)((unsigned long)addr & PAGE_MASK);
     size_t llen = (len + ((unsigned long)addr - (unsigned long)laddr) +
                    PAGE_SIZE - 1) & PAGE_MASK;
-    safe_munlock(laddr, llen);
+    return safe_munlock(laddr, llen);
 }
 
 static pthread_key_t hcall_buf_pkey;
diff -r 36bd4630ad99 tools/libxc/xc_private.h
--- a/tools/libxc/xc_private.h	Wed Aug 18 10:22:48 2010 +0200
+++ b/tools/libxc/xc_private.h	Wed Aug 18 16:39:11 2010 +0200
@@ -86,16 +86,19 @@ void xc_report_progress_step(xc_interfac
 void *xc_memalign(size_t alignment, size_t size);
 
 int lock_pages(void *addr, size_t len);
-void unlock_pages(void *addr, size_t len);
+int unlock_pages(void *addr, size_t len);
 
 int hcall_buf_prep(void **addr, size_t len);
 void hcall_buf_release(void **addr, size_t len);
 
-static inline void safe_munlock(const void *addr, size_t len)
+static inline int safe_munlock(const void *addr, size_t len)
 {
+    int err = 0;
     int saved_errno = errno;
-    (void)munlock(addr, len);
+    if (munlock(addr, len) == -1)
+        err = errno;
     errno = saved_errno;
+    return err;
 }
 
 int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall);