Use QEMU's standard VGA instead of virtio-vga

On Arch, -vga virtio needs qemu-hw-display-virtio-vga and also
qemu-hw-display-virtio-gpu, which that package doesn't depend on; with only
the first, QEMU segfaults at start without a message. The smoketest's VMs
are headless (or VNC), so -vga std, which qemu-base has, is enough. This
reverts 2207208's extra package and checks.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lib/common.sh

@@ -62,12 +62,6 @@ in_flatpak() {
   [ -f /.flatpak-info ] || [ -n "${FLATPAK_ID:-}" ]
 }
 
-# Whether QEMU has the display the smoketest's VMs start with (-vga virtio).
-# Arch packages it apart from qemu-base, as qemu-hw-display-virtio-vga.
-qemu_has_virtio_vga() {
-  [[ "$(qemu-system-x86_64 -device help 2> /dev/null)" == *'name "virtio-vga"'* ]]
-}
-
 # This project's folder
 sibling_dir() {
   cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd

lib/doctor.sh

@@ -50,15 +50,6 @@ cmd_doctor() {
     problem "not installed: ${missing[*]}" "fix: bash $(sibling_dir)/update.sh"
   fi
 
-  if command -v qemu-system-x86_64 &> /dev/null; then
-    if qemu_has_virtio_vga; then
-      ok "QEMU has the virtio-vga display the smoketest's VMs use"
-    else
-      problem "QEMU has no virtio-vga display, so the smoketest's VMs won't start" \
-        "fix: bash $(sibling_dir)/update.sh"
-    fi
-  fi
-
   if [ -r /dev/kvm ] && [ -w /dev/kvm ]; then
     ok "KVM is available for the smoketest's virtual machines"
   else

lib/smoketest.sh

@@ -56,8 +56,6 @@ require_vm_tools() {
     command -v "$tool" &> /dev/null \
       || die "$tool isn't installed. Install coredesktop-dev's packages: bash $(sibling_dir)/update.sh"
   done
-  qemu_has_virtio_vga \
-    || die "QEMU has no virtio-vga display. Install coredesktop-dev's packages: bash $(sibling_dir)/update.sh"
   [ -r "$KVM_DEVICE" ] && [ -w "$KVM_DEVICE" ] \
     || die "Can't use $KVM_DEVICE. Turn on virtualization (VT-x/AMD-V) in the firmware settings."
 }

lib/vm.sh

@@ -76,7 +76,7 @@ vm_start() {
     -drive "file=$disk,if=virtio,format=qcow2,discard=unmap" \
     -nic "user,model=virtio-net-pci,hostfwd=tcp:127.0.0.1:$VM_PORT-:22" \
     -virtfs "local,path=$PKG_CACHE,mount_tag=pkgcache,security_model=mapped-xattr" \
-    -vga virtio \
+    -vga std \
     "${display[@]}" \
     -serial "file:$VM_DIR/serial.log" \
     -pidfile "$VM_DIR/qemu.pid" \

tests/doctor.bats

@@ -71,15 +71,3 @@ load test_helper
   [[ "$output" == *"Usage: coredesktop-dev doctor"* ]]
   not_called flatpak-spawn
 }
-
-@test "doctor reports QEMU without the virtio-vga display" {
-  make_working_copy
-  stub qemu-system-x86_64 'echo "name \"VGA\", bus PCI"'
-  run cdd doctor
-  [ "$status" -eq 1 ]
-  [[ "$output" == *"PROBLEM  QEMU has no virtio-vga display"* ]]
-
-  stub qemu-system-x86_64 'echo "name \"virtio-vga\", bus PCI"'
-  run cdd doctor
-  [[ "$output" == *"ok       QEMU has the virtio-vga display"* ]]
-}

tests/install.bats

@@ -14,7 +14,7 @@ config() {
   [[ "$output" == *"is the deployed copy"* ]]
   [ "$(config)" = "WORKING_COPY=$(printf '%q' "$WC")" ]
   [ "$(readlink "$HOME/.local/bin/coredesktop-dev")" = "$PROJECT/bin/coredesktop-dev" ]
-  called install_packages shellcheck bats tea qemu-base qemu-hw-display-virtio-vga libisoburn
+  called install_packages shellcheck bats tea qemu-base libisoburn
 }
 
 @test "install refuses the deployed copy however it's spelled" {

tests/smoketest.bats

@@ -18,8 +18,7 @@ setup() {
   git -C "$WC" rev-parse HEAD > "$STATE/images/installed.ref"
 
   # A VM is a sleep that lets go of bats' output pipes
-  stub qemu-system-x86_64 '[ "$*" = "-device help" ] && { echo "name \"virtio-vga\", bus PCI"; exit; }
-    while [ $# -gt 0 ]; do [ "$1" = -pidfile ] && pidfile="$2"; shift; done
+  stub qemu-system-x86_64 'while [ $# -gt 0 ]; do [ "$1" = -pidfile ] && pidfile="$2"; shift; done
     /usr/bin/sleep 300 > /dev/null 2>&1 3>&- &
     echo $! > "$pidfile"'
   stub qemu-img 'touch "${@: -1}"'
@@ -99,16 +98,7 @@ last_run() {
   run cdd smoketest run 10 nosuch
   [ "$status" -eq 1 ]
   [[ "$output" == *"No scenario called nosuch"* ]]
-  # Only the check for the virtio-vga display, no VM
-  [ -z "$(grep '^qemu-system-x86_64 ' "$STUB_LOG" | grep -v -- '-device help')" ]
-}
-
-@test "run stops before any VM when QEMU has no virtio-vga display" {
-  stub qemu-system-x86_64 'echo "name \"VGA\", bus PCI"'
-  run cdd smoketest run 10
-  [ "$status" -eq 1 ]
-  [[ "$output" == *"QEMU has no virtio-vga display"* ]]
-  [ "$(grep -c '^qemu-system-x86_64 ' "$STUB_LOG")" -eq 1 ]
+  not_called qemu-system-x86_64
 }
 
 @test "each variant runs in its own VM" {
@@ -116,7 +106,7 @@ last_run() {
   [ "$status" -eq 0 ]
   [[ "$output" == *"PASS  30-variants @ one"* ]]
   [[ "$output" == *"PASS  30-variants @ two"* ]]
-  [ "$(grep '^qemu-system-x86_64 ' "$STUB_LOG" | grep -vc -- '-device help')" -eq 2 ]
+  [ "$(grep -c '^qemu-system-x86_64 ' "$STUB_LOG")" -eq 2 ]
   grep -q "variant two" "$(last_run)/30-variants@two/scenario.log"
 }
 

tests/update.bats

@@ -7,7 +7,7 @@ HOOK_MARKER="# Installed by coredesktop-dev; remove with: coredesktop-dev hooks
 @test "update installs the packages and links the command, without asking anything" {
   run bash "$PROJECT/update.sh" < /dev/null
   [ "$status" -eq 0 ]
-  called install_packages shellcheck bats tea qemu-base qemu-hw-display-virtio-vga libisoburn
+  called install_packages shellcheck bats tea qemu-base libisoburn
   [ "$(readlink "$HOME/.local/bin/coredesktop-dev")" = "$PROJECT/bin/coredesktop-dev" ]
 }
 

update.sh

@@ -16,7 +16,6 @@ PACKAGES=(
   bats         # make test
   tea          # Gitea's CLI, for pull requests
   qemu-base    # the smoketest's virtual machines
-  qemu-hw-display-virtio-vga  # the VM's -vga virtio (qemu-base leaves it out)
   libisoburn   # xorriso, for the smoketest VM's cloud-init disk
 )