qdev: add return value to init() callbacks.

Sorry folks, but it has to be.  One more of these invasive qdev patches.

We have a serious design bug in the qdev interface:  device init
callbacks can't signal failure because the init() callback has no
return value.  This patch fixes it.

We have already one case in-tree where this is needed:
Try -device virtio-blk-pci (without drive= specified) and watch qemu
segfault.  This patch fixes it.

With usb+scsi being converted to qdev we'll get more devices where the
init callback can fail for various reasons.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/hw/tcx.c b/hw/tcx.c
index 754751c..cb32070 100644
--- a/hw/tcx.c
+++ b/hw/tcx.c
@@ -515,7 +515,7 @@ static CPUWriteMemoryFunc * const tcx_dummy_write[3] = {
     tcx_dummy_writel,
 };
 
-static void tcx_init1(SysBusDevice *dev)
+static int tcx_init1(SysBusDevice *dev)
 {
     TCXState *s = FROM_SYSBUS(TCXState, dev);
     int io_memory, dummy_memory;
@@ -576,6 +576,7 @@ static void tcx_init1(SysBusDevice *dev)
     qemu_register_reset(tcx_reset, s);
     tcx_reset(s);
     qemu_console_resize(s->ds, s->width, s->height);
+    return 0;
 }
 
 static void tcx_screen_dump(void *opaque, const char *filename)