feat: add QEMU support documentation and enforce minimum version requirement

docs/dependencies/qemu.md

@@ -0,0 +1,28 @@
+# QEMU support
+
+GNS3 server requires QEMU 6.2 or newer. This is the minimum QEMU version that the server actively supports on Linux.
+
+For compatibility checks, the project evaluates the Linux distributions that are commonly used in server deployments and that still have supported releases: CentOS Stream, Debian, Fedora, openSUSE, RHEL, SLES, and Ubuntu LTS. Other distributions are assumed to ship similar package versions and are treated by the same rule: if the distro ships QEMU 6.2 or newer, it is considered compatible; if it ships an older version, it is not supported by GNS3 server.
+
+This document reflects the currently supported release set as of October 2026, based on the active releases listed by the major distro end-of-life trackers and package versions shipped by those releases.
+
+## Minimum supported version
+
+- Minimum supported QEMU version: 6.2
+- QEMU 6.2 was first shipped in Ubuntu 22.04 LTS and is the baseline used to determine whether a Linux distribution is suitable for GNS3 server.
+- Distributions shipping QEMU 6.2 or later are generally acceptable.
+- Older package versions are considered unsupported by policy.
+
+## Currently supported Linux releases and shipped QEMU versions
+
+The following supported releases are the current reference points used by the project. They are based on the active release lists published by the distributions' end-of-life trackers and the QEMU versions typically shipped by those releases.
+
+| Distribution | Current supported OS release(s) | QEMU version shipped | Source |
+| --- | --- | --- | --- |
+| Ubuntu LTS | 24.04 LTS, 22.04 LTS | 8.2 for 24.04, 6.2 for 22.04 | https://endoflife.date/ubuntu |
+| Debian | 13 (trixie), 12 (bookworm) | 9.x for 13, 7.2 for 12 | https://endoflife.date/debian |
+| Fedora | 42, 41, 40 | 9.x | https://endoflife.date/fedora |
+| openSUSE | Leap 15.6, Tumbleweed | 8.x to 9.x | https://endoflife.date/opensuse |
+| CentOS Stream | 10, 9 | 9.x / 8.x | https://endoflife.date/centos |
+| RHEL | 10, 9.5, 9.4 | 9.x / 8.x | https://endoflife.date/redhat-enterprise-linux |
+| SLES | 15 SP7, 15 SP6 | 8.x | https://endoflife.date/sles |

gns3server/compute/qemu/qemu_vm.py

@@ -2316,16 +2316,7 @@ class QemuVM(KernelDatapathMixin, BaseNode):
                     f"file={disk},if=none,id=drive{disk_index},index={disk_index},media=disk{extra_drive_options}",
                 ]
             )
-            if self._qemu_version and parse_version(self._qemu_version) >= parse_version("4.2.0"):
+            options.extend(["-device", f"ide-hd,drive=drive{disk_index},bus=ahci{disk_index}.0,id=drive{disk_index}"])
-                # The ‘ide-drive’ device is deprecated since version 4.2.0
-                # https://qemu.readthedocs.io/en/latest/system/deprecated.html#ide-drive-since-4-2
-                options.extend(
-                    ["-device", f"ide-hd,drive=drive{disk_index},bus=ahci{disk_index}.0,id=drive{disk_index}"]
-                )
-            else:
-                options.extend(
-                    ["-device", f"ide-drive,drive=drive{disk_index},bus=ahci{disk_index}.0,id=drive{disk_index}"]
-                )
         elif interface == "nvme":
             options.extend(
                 [
@@ -2721,15 +2712,12 @@ class QemuVM(KernelDatapathMixin, BaseNode):
 
     async def _disable_graphics(self):
         """
-        Disable graphics depending of the QEMU version
+        Disable graphics for Qemu if no graphics options are specified.
         """
 
         if any(opt in self._options for opt in ["-display", "-nographic", "-curses", "-sdl-spice", "-vnc"]):
             return []
-        if self._qemu_version and parse_version(self._qemu_version) >= parse_version("3.0"):
+        return ["-display", "none"]
-            return ["-display", "none"]
-        else:
-            return ["-nographic"]
 
     async def _run_with_hardware_acceleration(self, qemu_path, options):
         """
@@ -2854,8 +2842,8 @@ class QemuVM(KernelDatapathMixin, BaseNode):
         """
 
         self._qemu_version = await self.manager.get_qemu_version(self.qemu_path)
-        if self._qemu_version and parse_version(self._qemu_version) < parse_version("2.4.0"):
+        if self._qemu_version and parse_version(self._qemu_version) < parse_version("6.2.0"):
-            raise QemuError("Qemu version 2.4 or later is required to run Qemu VMs")
+            raise QemuError("Qemu version 6.2 or later is required to run Qemu VMs")
         vm_name = self._name.replace(",", ",,")
         project_path = self.project.path.replace(",", ",,")
         additional_options = self._options.strip()
@@ -2877,14 +2865,6 @@ class QemuVM(KernelDatapathMixin, BaseNode):
         if await self._run_with_hardware_acceleration(self.qemu_path, self._options):
             if sys.platform.startswith("linux"):
                 command.extend(["-enable-kvm"])
-                # Issue on some combo Intel CPU + KVM + Qemu 2.4.0
-                # https://github.com/GNS3/gns3-server/issues/685
-                if (
-                    self._qemu_version
-                    and parse_version(self._qemu_version) >= parse_version("2.4.0")
-                    and self.platform == "x86_64"
-                ):
-                    command.extend(["-machine", "smm=off"])
             elif sys.platform.startswith("darwin"):
                 command.extend(["-enable-hax"])
         command.extend(["-boot", f"order={self._boot_priority}"])

tests/compute/qemu/test_qemu_vm.py

@@ -645,7 +645,7 @@ async def test_build_command_console_none(vm):
 @pytest.mark.asyncio
 async def test_build_command_manual_uuid(vm):
     """
-    If user has set a uuid we keep it
+    If user has set a UUID we keep it
     """
 
     vm.options = "-uuid e1c307a4-896f-11e6-81a5-3c07547807cc"
@@ -657,75 +657,34 @@ async def test_build_command_manual_uuid(vm):
 
 
 @pytest.mark.asyncio
-async def test_build_command_kvm_below_2_4(linux_platform, vm, fake_qemu_binary):
+async def test_build_command_kvm_below_6_2(linux_platform, vm, fake_qemu_binary):
     """
     Qemu 2.4 introduce an issue with KVM
     """
 
-    vm.manager.get_qemu_version = AsyncioMagicMock(return_value="2.3.2")
+    vm.manager.get_qemu_version = AsyncioMagicMock(return_value="6.1.0")
     with asyncio_patch("gns3server.compute.qemu.qemu_vm.QemuVM._run_with_hardware_acceleration", return_value=True):
         with asyncio_patch("asyncio.create_subprocess_exec", return_value=MagicMock()):
             with pytest.raises(QemuError):
                 await vm._build_command()
 
 
-@pytest.mark.asyncio
-async def test_build_command_kvm_2_4(linux_platform, vm, fake_qemu_binary):
-    """
-    Qemu 2.4 introduce an issue with KVM
-    """
-
-    vm.manager.get_qemu_version = AsyncioMagicMock(return_value="2.4.2")
-    os.environ["DISPLAY"] = "0:0"
-    with asyncio_patch("gns3server.compute.qemu.qemu_vm.QemuVM._run_with_hardware_acceleration", return_value=True):
-        with asyncio_patch("asyncio.create_subprocess_exec", return_value=MagicMock()) as process:
-            cmd = await vm._build_command()
-            nio = vm._local_udp_tunnels[0][0]
-            assert cmd == [
-                fake_qemu_binary,
-                "-name",
-                "test",
-                "-m",
-                "256M",
-                "-smp",
-                "cpus=1,maxcpus=1,sockets=1",
-                "-enable-kvm",
-                "-machine",
-                "smm=off",
-                "-boot",
-                "order=c",
-                "-uuid",
-                vm.id,
-                "-serial",
-                f"telnet:127.0.0.1:{vm._internal_console_port},server,nowait",
-                "-net",
-                "none",
-                "-device",
-                "i82801b11-bridge,id=dmi_pci_bridge1",
-                "-device",
-                "pci-bridge,id=pci-bridge1,bus=dmi_pci_bridge1,chassis_nr=0x1,addr=0x1,shpc=off",
-                "-device",
-                f"e1000,mac={vm._mac_address},bus=pci-bridge1,addr=0x00,netdev=gns3-0",
-                "-netdev",
-                f"socket,id=gns3-0,udp=127.0.0.1:{nio.rport},localaddr=127.0.0.1:{nio.lport}",
-                "-nographic",
-            ]
-
-
 @pytest.mark.asyncio
 async def test_build_command_without_display(vm):
 
-    vm.manager.get_qemu_version = AsyncioMagicMock(return_value="2.5.0")
+    vm.manager.get_qemu_version = AsyncioMagicMock(return_value="6.2.0")
     os.environ["DISPLAY"] = ""
     with asyncio_patch("asyncio.create_subprocess_exec", return_value=MagicMock()):
         cmd = await vm._build_command()
-        assert "-nographic" in cmd
+        print(cmd)
+        assert "-display" in cmd
+        assert "none" in cmd
 
 
 @pytest.mark.asyncio
 async def test_build_command_two_adapters(vm, fake_qemu_binary):
 
-    vm.manager.get_qemu_version = AsyncioMagicMock(return_value="2.5.0")
+    vm.manager.get_qemu_version = AsyncioMagicMock(return_value="6.2.0")
     os.environ["DISPLAY"] = "0:0"
     vm.adapters = 2
     with asyncio_patch("asyncio.create_subprocess_exec", return_value=MagicMock()):
@@ -760,7 +719,8 @@ async def test_build_command_two_adapters(vm, fake_qemu_binary):
             f"e1000,mac={int_to_macaddress(macaddress_to_int(vm._mac_address) + 1)},bus=pci-bridge1,addr=0x01,netdev=gns3-1",
             "-netdev",
             f"socket,id=gns3-1,udp=127.0.0.1:{nio2.rport},localaddr=127.0.0.1:{nio2.lport}",
-            "-nographic",
+            "-display",
+            "none",
         ]