diff options
-rw-r--r-- | hw/block/xen-block.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c index a07cd7e..bfa5396 100644 --- a/hw/block/xen-block.c +++ b/hw/block/xen-block.c @@ -115,9 +115,13 @@ static void xen_block_connect(XenDevice *xendev, Error **errp) return; } - if (xen_device_frontend_scanf(xendev, "protocol", "%ms", - &str) != 1) { - protocol = BLKIF_PROTOCOL_NATIVE; + if (xen_device_frontend_scanf(xendev, "protocol", "%ms", &str) != 1) { + /* x86 defaults to the 32-bit protocol even for 64-bit guests. */ + if (object_dynamic_cast(OBJECT(qdev_get_machine()), "x86-machine")) { + protocol = BLKIF_PROTOCOL_X86_32; + } else { + protocol = BLKIF_PROTOCOL_NATIVE; + } } else { if (strcmp(str, XEN_IO_PROTO_ABI_X86_32) == 0) { protocol = BLKIF_PROTOCOL_X86_32; |