diff --git a/xCAT-server/lib/xcat/plugins/kvm.pm b/xCAT-server/lib/xcat/plugins/kvm.pm
index 0bae3a15e..27ba53551 100644
--- a/xCAT-server/lib/xcat/plugins/kvm.pm
+++ b/xCAT-server/lib/xcat/plugins/kvm.pm
@@ -551,13 +551,16 @@ sub build_diskstruct {
                     $tdiskhash->{driver}->{type}  = $disks{$_}->{format};
                     $tdiskhash->{driver}->{cache} = $cachemethod;
                     $tdiskhash->{source}->{file}  = $_;
-                    $tdiskhash->{target}->{dev}   = $disks{$_}->{device};
+                    my $device = $disks{$_}->{device};
+                    $tdiskhash->{target}->{dev}   = $device;
 
-                    if ($disks{$_} =~ /^vd/) {
+                    # libvirt reads the bus out of the device name when the disk states
+                    # none: hd* is ide, sd* is scsi, vd* is virtio. State the same bus.
+                    if ($device =~ /^vd/) {
                         $tdiskhash->{target}->{bus} = 'virtio';
-                    } elsif ($disks{$_} =~ /^hd/) {
+                    } elsif ($device =~ /^hd/) {
                         $tdiskhash->{target}->{bus} = 'ide';
-                    } elsif ($disks{$_} =~ /^sd/) {
+                    } elsif ($device =~ /^sd/) {
                         $tdiskhash->{target}->{bus} = 'scsi';
                     }
                     push @returns, $tdiskhash;
diff --git a/xCAT-test/unit/kvm_diskstruct_bus.t b/xCAT-test/unit/kvm_diskstruct_bus.t
new file mode 100644
index 000000000..2087c9975
--- /dev/null
+++ b/xCAT-test/unit/kvm_diskstruct_bus.t
@@ -0,0 +1,90 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+
+use FindBin;
+use Test::More;
+
+# The scratch package below declares these; the test names them once each.
+no warnings 'once';
+
+my $source = "$FindBin::Bin/../../xCAT-server/lib/xcat/plugins/kvm.pm";
+open(my $source_fh, '<', $source) or die "open $source: $!";
+my $content = do { local $/; <$source_fh> };
+close($source_fh) or die "close $source: $!";
+
+my @routines;
+for my $name (qw(build_diskstruct guest_arch_profile getUnits)) {
+    my ($routine) = $content =~ /^(sub \Q$name\E\s*\{.*?^\})/ms;
+    BAIL_OUT("could not extract $name from kvm.pm") unless $routine;
+    push(@routines, $routine);
+}
+
+# kvm.pm needs a management node to load, so the disk builder runs in a scratch package.
+# get_multiple_paths_by_url is the only routine it calls that reaches libvirt; it answers
+# from $pool, which holds what a storage pool reports for one node.
+my $harness = <<'PERL';
+package KVMDisk;
+our ($node, $confdata, $pool);
+sub get_multiple_paths_by_url { return $pool; }
+PERL
+
+eval $harness . join("\n", @routines) . "\n1;\n";    ## no critic (BuiltinFunctions::ProhibitStringyEval)
+BAIL_OUT("could not load the kvm disk builder: $@") if $@;
+
+# Build the disks of a node of $arch whose vmstorage is a libvirt pool holding the volumes
+# in $pool: a path => { device, format } map, the shape get_multiple_paths_by_url returns.
+sub pool_disks {
+    my ($arch, $pool) = @_;
+    local $KVMDisk::node     = 'cn1';
+    local $KVMDisk::confdata = {
+        vm => { cn1 => [ {
+            host         => 'hyp1',
+            storage      => 'dir:///var/lib/libvirt/images/',
+            storagecache => 'writeback',
+        } ] },
+        nodetype => { cn1 => [ { arch => $arch } ] },
+        hyp1     => { cpumodel => 'x86_64' },
+    };
+    local $KVMDisk::pool = $pool;
+    my $chatter = '';
+    my $disks;
+    {
+        open(my $capture, '>', \$chatter) or die "capture stdout: $!";
+        local *STDOUT = $capture;
+        ($disks) = KVMDisk::build_diskstruct(undef);
+    }
+    BAIL_OUT('build_diskstruct returned no disks') unless ref $disks eq 'ARRAY';
+    return $disks;
+}
+
+# One volume in the pool, named <node>.<device>.<format>. The disk is the first element;
+# the optical drive build_diskstruct always appends is the second.
+sub pool_disk {
+    my ($arch, $device) = @_;
+    my $path = "/var/lib/libvirt/images/cn1.$device.qcow2";
+    return pool_disks($arch, { $path => { device => $device, format => 'qcow2' } })->[0];
+}
+
+# A disk on a libvirt storage pool states the bus of the device name it is given. libvirt
+# reads the same names the same way: hd* is ide, sd* is scsi, vd* is virtio.
+is(pool_disk('x86_64', 'hda')->{target}->{bus}, 'ide',
+    'an hd* disk on a storage pool is ide');
+is(pool_disk('x86_64', 'sda')->{target}->{bus}, 'scsi',
+    'an sd* disk on a storage pool is scsi');
+is(pool_disk('x86_64', 'vda')->{target}->{bus}, 'virtio',
+    'a vd* disk on a storage pool is virtio');
+
+# The device name is the name of the volume in the pool, and stays it. The riscv64 virt
+# machine has no IDE controller, so a riscv64 node depends on that name being sd*.
+my $riscv = pool_disk('riscv64', 'sda');
+is($riscv->{target}->{dev}, 'sda', 'a riscv64 pool disk keeps the sd* name of its volume');
+is($riscv->{target}->{bus}, 'scsi', 'a riscv64 pool disk is scsi, not ide');
+
+my $riscv_all = pool_disks('riscv64',
+    { '/var/lib/libvirt/images/cn1.sda.qcow2' => { device => 'sda', format => 'qcow2' } });
+is($riscv_all->[1]->{device}, 'cdrom', 'the riscv64 guest still gets an optical drive');
+like($riscv_all->[1]->{target}->{dev}, qr/^sd/,
+    'the riscv64 optical drive is named sd*, not hd*');
+
+done_testing();