diff --git a/test/TEST-36-NUMAPOLICY/test.sh b/test/TEST-36-NUMAPOLICY/test.sh
index 7909b1dce3..a0bfd4079a 100755
--- a/test/TEST-36-NUMAPOLICY/test.sh
+++ b/test/TEST-36-NUMAPOLICY/test.sh
@@ -9,7 +9,7 @@ TEST_NO_NSPAWN=1
 . "${TEST_BASE_DIR:?}/test-functions"
 
 if qemu_min_version "5.2.0"; then
-    QEMU_OPTIONS="-object memory-backend-ram,id=mem0,size=${QEMU_MEM:-512M} -numa node,memdev=mem0,nodeid=0"
+    QEMU_OPTIONS="-object memory-backend-ram,id=mem0,size=${QEMU_MEM:-768M} -numa node,memdev=mem0,nodeid=0"
 else
     QEMU_OPTIONS="-numa node,nodeid=0"
 fi
diff --git a/test/TEST-64-UDEV-STORAGE/deny-list-ubuntu-ci b/test/TEST-64-UDEV-STORAGE/deny-list-ubuntu-ci
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/test/TEST-64-UDEV-STORAGE/test.sh b/test/TEST-64-UDEV-STORAGE/test.sh
index fe80434309..80c60f19f7 100755
--- a/test/TEST-64-UDEV-STORAGE/test.sh
+++ b/test/TEST-64-UDEV-STORAGE/test.sh
@@ -20,11 +20,6 @@ QEMU_TIMEOUT="${QEMU_TIMEOUT:-600}"
 USER_QEMU_OPTIONS="${QEMU_OPTIONS:-}"
 USER_KERNEL_APPEND="${KERNEL_APPEND:-}"
 
-if ! get_bool "$QEMU_KVM"; then
-    echo "This test requires KVM, skipping..."
-    exit 0
-fi
-
 _host_has_feature() {(
     set -e
 
@@ -213,6 +208,11 @@ testcase_nvme_basic() {
 
 # Test for issue https://github.com/systemd/systemd/issues/20212
 testcase_virtio_scsi_identically_named_partitions() {
+    if ! get_bool "$QEMU_KVM"; then
+        echo "This test requires KVM, skipping..."
+        return 77
+    fi
+
     if ! "${QEMU_BIN:?}" -device help | grep 'name "virtio-scsi-pci"'; then
         echo "virtio-scsi-pci device driver is not available, skipping test..."
         return 77
@@ -286,8 +286,8 @@ EOF
     mkfs.ext4 -U "deadbeef-dead-dead-beef-111111111111" -L "failover_vol" "${lodev}p2"
     losetup -d "$lodev"
 
-    # Add 64 multipath devices, each backed by 4 paths
-    for ndisk in {0..63}; do
+    # Add 16 multipath devices, each backed by 4 paths
+    for ndisk in {0..15}; do
         wwn="0xDEADDEADBEEF$(printf "%.4d" "$ndisk")"
         # Use a partitioned disk for the first device to test failover
         [[ $ndisk -eq 0 ]] && image="$partdisk" || image="${TESTDIR:?}/disk$ndisk.img"
diff --git a/test/test-functions b/test/test-functions
index 3cdfd800f0..359eb90314 100644
--- a/test/test-functions
+++ b/test/test-functions
@@ -92,7 +92,7 @@ add_at_exit_handler() {
 # check if it's not explicitly disabled (TEST_NO_KVM) and we're not already
 # running under KVM. If these conditions are met, enable KVM (and possibly
 # nested KVM), otherwise disable it.
-if get_bool "${TEST_NESTED_KVM:=}" || (! get_bool "${TEST_NO_KVM:=}" && [[ "$(systemd-detect-virt -v)" != kvm ]]); then
+if get_bool "${TEST_NESTED_KVM:=}" || (! get_bool "${TEST_NO_KVM:=}" && ! systemd-detect-virt -v); then
     QEMU_KVM=yes
 else
     QEMU_KVM=no
@@ -483,7 +483,7 @@ run_qemu() {
     qemu_options+=(
         -smp "$QEMU_SMP"
         -net none
-        -m "${QEMU_MEM:-512M}"
+        -m "${QEMU_MEM:-768M}"
         -nographic
         -kernel "$KERNEL_BIN"
         -drive "format=raw,cache=unsafe,file=$image"
diff --git a/test/units/testsuite-64.sh b/test/units/testsuite-64.sh
index 05a012b2b1..3ae1bddaf4 100755
--- a/test/units/testsuite-64.sh
+++ b/test/units/testsuite-64.sh
@@ -82,7 +82,7 @@ EOF
     udevadm settle
     ls -l /dev/disk/by-id/
 
-    for i in {0..63}; do
+    for i in {0..15}; do
         wwid="deaddeadbeef$(printf "%.4d" "$i")"
         path="/dev/disk/by-id/wwn-0x$wwid"
         dmpath="$(readlink -f "$path")"
@@ -178,7 +178,7 @@ EOF
     # leading to dead symlinks in /dev/disk/
     iterations=100
     timeout=30
-    if [[ -n "${ASAN_OPTIONS:-}" ]]; then
+    if [[ -n "${ASAN_OPTIONS:-}" ]] || [[ "$(systemd-detect-virt -v)" == "qemu" ]]; then
         iterations=10
         timeout=180
     fi