diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index c7e78266e50e84810d5ecb48071d077fd39a3c3a..a8fce222067dccd5e9e1b5667b090768e9c873c6 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -4211,9 +4211,26 @@ qemuBuildDriveDevStr(virDomainDefPtr def,
             virBufferAddLit(&opt, "ide-drive");
         }
 
-        virBufferAsprintf(&opt, ",bus=ahci%d.%d",
-                          disk->info.addr.drive.controller,
-                          disk->info.addr.drive.unit);
+        if (qemuDomainMachineIsQ35(def) &&
+            disk->info.addr.drive.controller == 0) {
+            /* Q35 machines have an implicit ahci (sata) controller at
+             * 00:1F.2 which has no "id" associated with it. For this
+             * reason, we can't refer to it as "ahci0". Instead, we
+             * don't give an id, which qemu interprets as "use the
+             * first ahci controller". We then need to specify the
+             * unit with "unit=%d" rather than adding it onto the bus
+             * arg.
+             */
+            virBufferAsprintf(&opt, ",unit=%d", disk->info.addr.drive.unit);
+        } else {
+            /* All other ahci controllers have been created by
+             * libvirt, so they *do* have an id, and we can identify
+             * them that way.
+             */
+            virBufferAsprintf(&opt, ",bus=ahci%d.%d",
+                              disk->info.addr.drive.controller,
+                              disk->info.addr.drive.unit);
+        }
         break;
     case VIR_DOMAIN_DISK_BUS_VIRTIO:
         if (disk->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_CCW) {
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-q35.args b/tests/qemuxml2argvdata/qemuxml2argv-q35.args
index 5ff4bc7b60e17ec70230f79c664c27fe34c3e3ae..9e67be566071e66fb11a3e4774745b0e789544ca 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-q35.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-q35.args
@@ -3,4 +3,6 @@ LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test \
 -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c \
 -device i82801b11-bridge,id=pci.1,bus=pcie.0,addr=0x2 \
 -device pci-bridge,chassis_nr=2,id=pci.2,bus=pci.1,addr=0x1 \
+-drive file=/dev/HostVG/QEMUGuest1,if=none,id=drive-sata0-0-0 \
+-device ide-drive,unit=0,drive=drive-sata0-0-0,id=sata0-0-0 \
 -vga qxl -global qxl.ram_size=67108864 -global qxl.vram_size=18874368
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-q35.xml b/tests/qemuxml2argvdata/qemuxml2argv-q35.xml
index 3541b146af4242adff8390cd2307909242ce2731..edaf6cbbf03dad394fa236c32dff530a46911656 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-q35.xml
+++ b/tests/qemuxml2argvdata/qemuxml2argv-q35.xml
@@ -14,6 +14,11 @@
   <on_crash>destroy</on_crash>
   <devices>
     <emulator>/usr/libexec/qemu-kvm</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='sda' bus='sata'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
     <controller type='pci' index='0' model='pcie-root'/>
     <controller type='pci' index='1' model='dmi-to-pci-bridge'/>
     <controller type='pci' index='2' model='pci-bridge'/>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 0068d27ed2f9254dfc1ebcbce9c0d909105162a5..679124e35b52dc754a837dec72a71cf131ad2346 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -1001,7 +1001,7 @@ mymain(void)
     DO_TEST("q35",
             QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_PCI_BRIDGE,
             QEMU_CAPS_DEVICE_DMI_TO_PCI_BRIDGE,
-            QEMU_CAPS_ICH9_AHCI,
+            QEMU_CAPS_DRIVE, QEMU_CAPS_ICH9_AHCI,
             QEMU_CAPS_VGA, QEMU_CAPS_DEVICE_VIDEO_PRIMARY,
             QEMU_CAPS_VGA, QEMU_CAPS_VGA_QXL, QEMU_CAPS_DEVICE_QXL);
 
diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-q35.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-q35.xml
index 2a86e61f5701fcb170ac23309bf84da70d47d3ef..96f8eafdce24ab79f0bb94d83441fb4910379558 100644
--- a/tests/qemuxml2xmloutdata/qemuxml2xmlout-q35.xml
+++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-q35.xml
@@ -14,6 +14,11 @@
   <on_crash>destroy</on_crash>
   <devices>
     <emulator>/usr/libexec/qemu-kvm</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='sda' bus='sata'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
     <controller type='pci' index='0' model='pcie-root'/>
     <controller type='pci' index='1' model='dmi-to-pci-bridge'/>
     <controller type='pci' index='2' model='pci-bridge'/>