1 files changed, 20 insertions, 5 deletions
diff --git a/util/memfd.c b/util/memfd.c
index 4a3c07e..07beab1 100644
--- a/util/memfd.c
+++ b/util/memfd.c
@@ -28,6 +28,7 @@
 #include "qemu/osdep.h"
 
 #include "qapi/error.h"
+#include "qemu/error-report.h"
 #include "qemu/memfd.h"
 #include "qemu/host-utils.h"
 
@@ -149,11 +150,15 @@ err:
 void qemu_memfd_free(void *ptr, size_t size, int fd)
 {
     if (ptr) {
-        munmap(ptr, size);
+        if (munmap(ptr, size) != 0) {
+            error_report("memfd munmap() failed: %s", strerror(errno));
+        }
     }
 
     if (fd != -1) {
-        close(fd);
+        if (close(fd) != 0) {
+            error_report("memfd close() failed: %s", strerror(errno));
+        }
     }
 }
 
@@ -189,17 +194,27 @@ bool qemu_memfd_alloc_check(void)
 /**
  * qemu_memfd_check():
  *
- * Check if host supports memfd.
+ * Check if host supports memfd.  Cache the answer for the common case flags=0.
  */
 bool qemu_memfd_check(unsigned int flags)
 {
 #ifdef CONFIG_LINUX
-    int mfd = memfd_create("test", flags | MFD_CLOEXEC);
+    int mfd;
+    static int memfd_check = MEMFD_TODO;
 
+    if (!flags && memfd_check != MEMFD_TODO) {
+        return memfd_check;
+    }
+
+    mfd = memfd_create("test", flags | MFD_CLOEXEC);
     if (mfd >= 0) {
         close(mfd);
-        return true;
     }
+    if (!flags) {
+        memfd_check = (mfd >= 0) ? MEMFD_OK : MEMFD_KO;
+    }
+    return (mfd >= 0);
+
 #endif
 
     return false;