diff -aur kvm-64.old/qemu/hw/scsi-disk.c kvm-64.new/qemu/hw/scsi-disk.c
--- kvm-64.old/qemu/hw/scsi-disk.c	2008-03-26 08:49:35.000000000 -0400
+++ kvm-64.new/qemu/hw/scsi-disk.c	2008-03-30 08:37:25.000000000 -0400
@@ -196,12 +196,12 @@
         n = SCSI_DMA_BUF_SIZE / 512;
 
     r->buf_len = n * 512;
-    r->aiocb = bdrv_aio_read(s->bdrv, r->sector, r->dma_buf, n,
+    r->sector += n;
+    r->sector_count -= n;
+    r->aiocb = bdrv_aio_read(s->bdrv, r->sector - n, r->dma_buf, n,
                              scsi_read_complete, r);
     if (r->aiocb == NULL)
         scsi_command_complete(r, SENSE_HARDWARE_ERROR);
-    r->sector += n;
-    r->sector_count -= n;
 }
 
 static void scsi_write_complete(void * opaque, int ret)
@@ -248,12 +248,12 @@
         BADF("Data transfer already in progress\n");
     n = r->buf_len / 512;
     if (n) {
-        r->aiocb = bdrv_aio_write(s->bdrv, r->sector, r->dma_buf, n,
+        r->sector += n;
+        r->sector_count -= n;
+        r->aiocb = bdrv_aio_write(s->bdrv, r->sector - n, r->dma_buf, n,
                                   scsi_write_complete, r);
         if (r->aiocb == NULL)
             scsi_command_complete(r, SENSE_HARDWARE_ERROR);
-        r->sector += n;
-        r->sector_count -= n;
     } else {
         /* Invoke completion routine to fetch data from host.  */
         scsi_write_complete(r, 0);