[Qemu-devel] [PATCH for-2.11] hw/misc/ivshmem: Fix ivshmem_recv_msg() to also work on big endian systems

[Thomas Huth <thuth@redhat.com>]

The "slow" ivshmem-tests currently fail when they are running on a
big endian host:

$ uname -m
ppc64
$ V=1 QTEST_QEMU_BINARY=x86_64-softmmu/qemu-system-x86_64 tests/ivshmem-test -m slow
/x86_64/ivshmem/single: OK
/x86_64/ivshmem/hotplug: OK
/x86_64/ivshmem/memdev: OK
/x86_64/ivshmem/pair: OK
/x86_64/ivshmem/server-msi: qemu-system-x86_64:
 -device ivshmem-doorbell,chardev=chr0,vectors=2: server sent invalid ID message
Broken pipe

The problem is that the server side code in ivshmem_server_send_one_msg()
correctly translates all messages IDs into little endian 64-bit values,
but the client side code in the ivshmem_recv_msg() function does not swap
the byte order back. Fix it by passing the value through le64_to_cpu().

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 hw/misc/ivshmem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index 47a015f..b3ef3ec 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -653,7 +653,7 @@ static int64_t ivshmem_recv_msg(IVShmemState *s, int *pfd, Error **errp)
     } while (n < sizeof(msg));
 
     *pfd = qemu_chr_fe_get_msgfd(&s->server_chr);
-    return msg;
+    return le64_to_cpu(msg);
 }
 
 static void ivshmem_recv_setup(IVShmemState *s, Error **errp)
-- 
1.8.3.1