diff -r -u source.bak/include/hw/block/block.h source/include/hw/block/block.h
--- source.bak/include/hw/block/block.h	2015-11-03 02:27:23.000000000 -0500
+++ source/include/hw/block/block.h	2017-06-27 11:11:11.498111140 -0400
@@ -20,7 +20,7 @@
     BlockBackend *blk;
     uint16_t physical_block_size;
     uint16_t logical_block_size;
-    uint16_t min_io_size;
+    uint32_t min_io_size;
     uint32_t opt_io_size;
     int32_t bootindex;
     uint32_t discard_granularity;
@@ -47,7 +47,7 @@
                           _conf.logical_block_size),                    \
     DEFINE_PROP_BLOCKSIZE("physical_block_size", _state,                \
                           _conf.physical_block_size),                   \
-    DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 0),  \
+    DEFINE_PROP_UINT32("min_io_size", _state, _conf.min_io_size, 0),  \
     DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0),    \
     DEFINE_PROP_UINT32("discard_granularity", _state, \
                        _conf.discard_granularity, -1)
diff -r -u source.bak/include/standard-headers/linux/virtio_blk.h source/include/standard-headers/linux/virtio_blk.h
--- source.bak/include/standard-headers/linux/virtio_blk.h	2015-11-03 02:27:23.000000000 -0500
+++ source/include/standard-headers/linux/virtio_blk.h	2017-06-27 11:11:26.550111138 -0400
@@ -74,7 +74,7 @@
 	/* alignment offset in logical blocks. */
 	uint8_t alignment_offset;
 	/* minimum I/O size without performance penalty in logical blocks. */
-	uint16_t min_io_size;
+	uint32_t min_io_size;
 	/* optimal sustained I/O size in logical blocks. */
 	uint32_t opt_io_size;
 
diff -r -u source.bak/pc-bios/s390-ccw/virtio.h source/pc-bios/s390-ccw/virtio.h
--- source.bak/pc-bios/s390-ccw/virtio.h	2015-12-12 07:16:02.000000000 -0500
+++ source/pc-bios/s390-ccw/virtio.h	2017-06-27 11:11:41.178111136 -0400
@@ -177,7 +177,7 @@
     /* the next 4 entries are guarded by VIRTIO_BLK_F_TOPOLOGY  */
     u8 physical_block_exp; /* exponent for physical block per logical block */
     u8 alignment_offset;   /* alignment offset in logical blocks */
-    u16 min_io_size;       /* min I/O size without performance penalty
+    u32 min_io_size;       /* min I/O size without performance penalty
                               in logical blocks */
     u32 opt_io_size;       /* optimal sustained I/O size in logical blocks */