kvm tools: Fix test for mmap failure

On error mmap returns MAP_FAILED so we need a proper test here.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/hw/pci-shmem.c b/tools/kvm/hw/pci-shmem.c
index 8bac15180a629c12a7c5cd324c810f40439c22d0..ac2d264cf733a690bf3d3c3ec1e49fefe91d8b80 100644 (file)
--- a/tools/kvm/hw/pci-shmem.c
+++ b/tools/kvm/hw/pci-shmem.c
@@ -207,10 +207,11 @@ static void *setup_shmem(const char *key, size_t len, int creating)
        }
        mem = mmap(NULL, len,
                   PROT_READ | PROT_WRITE, MAP_SHARED | MAP_NORESERVE, fd, 0);
-       close(fd);
-
-       if (mem == NULL)
+       if (mem == MAP_FAILED) {
                pr_warning("Failed to mmap shared memory file");
+               mem = NULL;
+       }
+       close(fd);
 
        return mem;
 }