From: Pavel Hrdina <phrdina@redhat.com>

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
---
 src/qemu/qemu_process.c                       | 12 ++--
 src/qemu/qemu_processpriv.h                   |  2 +
 .../iommufd-q35-fd.x86_64-latest.args         | 41 +++++++++++++
 .../iommufd-q35-fd.x86_64-latest.xml          | 60 +++++++++++++++++++
 tests/qemuxmlconfdata/iommufd-q35-fd.xml      | 38 ++++++++++++
 tests/qemuxmlconftest.c                       |  9 ++-
 6 files changed, 157 insertions(+), 5 deletions(-)
 create mode 100644 tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.args
 create mode 100644 tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.xml
 create mode 100644 tests/qemuxmlconfdata/iommufd-q35-fd.xml

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index c78fb4273c..14bc88b5cc 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -7751,7 +7751,7 @@ qemuProcessOpenIommuFd(virDomainObj *vm)
  *
  * Returns: 0 on success, -1 on failure
  */
-static int
+int
 qemuProcessPrepareIommuFd(virDomainObj *vm)
 {
     qemuDomainObjPrivate *priv = vm->privateData;
@@ -7771,10 +7771,14 @@ qemuProcessPrepareIommuFd(virDomainObj *vm)
         return -1;
     }
 
-    iommufd = dup(fdt->fds[0]);
+    if (fdt->testfds) {
+        iommufd = dup2(fdt->fds[0], fdt->testfds[0]);
+    } else {
+        iommufd = dup(fdt->fds[0]);
 
-    if (qemuSecuritySetImageFDLabel(priv->driver->securityManager, vm->def, iommufd) < 0)
-        return -1;
+        if (qemuSecuritySetImageFDLabel(priv->driver->securityManager, vm->def, iommufd) < 0)
+            return -1;
+    }
 
     priv->iommufd = qemuFDPassDirectNew("iommufd", &iommufd);
 
diff --git a/src/qemu/qemu_processpriv.h b/src/qemu/qemu_processpriv.h
index 0ba5897f40..39cb7dd0dc 100644
--- a/src/qemu/qemu_processpriv.h
+++ b/src/qemu/qemu_processpriv.h
@@ -37,3 +37,5 @@ void qemuProcessHandleDeviceDeleted(qemuMonitor *mon,
                                     const char *devAlias);
 
 int qemuProcessQMPInitMonitor(qemuMonitor *mon);
+
+int qemuProcessPrepareIommuFd(virDomainObj *vm);
diff --git a/tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.args b/tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.args
new file mode 100644
index 0000000000..7df3d173f3
--- /dev/null
+++ b/tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.args
@@ -0,0 +1,41 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/var/lib/libvirt/qemu/domain--1-q35-test \
+USER=test \
+LOGNAME=test \
+XDG_DATA_HOME=/var/lib/libvirt/qemu/domain--1-q35-test/.local/share \
+XDG_CACHE_HOME=/var/lib/libvirt/qemu/domain--1-q35-test/.cache \
+XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain--1-q35-test/.config \
+/usr/bin/qemu-system-x86_64 \
+-name guest=q35-test,debug-threads=on \
+-S \
+-object '{"qom-type":"secret","id":"masterKey0","format":"raw","file":"/var/lib/libvirt/qemu/domain--1-q35-test/master-key.aes"}' \
+-machine q35,usb=off,dump-guest-core=off,memory-backend=pc.ram,acpi=off \
+-accel tcg \
+-cpu qemu64 \
+-m size=2097152k \
+-object '{"qom-type":"memory-backend-ram","id":"pc.ram","size":2147483648}' \
+-overcommit mem-lock=off \
+-smp 2,sockets=2,cores=1,threads=1 \
+-uuid 11dbdcdd-4c3b-482b-8903-9bdb8c0a2774 \
+-display none \
+-no-user-config \
+-nodefaults \
+-chardev socket,id=charmonitor,fd=1729,server=on,wait=off \
+-mon chardev=charmonitor,id=monitor,mode=control \
+-rtc base=utc \
+-no-shutdown \
+-boot strict=on \
+-device '{"driver":"pcie-root-port","port":16,"chassis":1,"id":"pci.1","bus":"pcie.0","multifunction":true,"addr":"0x2"}' \
+-device '{"driver":"pcie-root-port","port":17,"chassis":2,"id":"pci.2","bus":"pcie.0","addr":"0x2.0x1"}' \
+-device '{"driver":"qemu-xhci","id":"usb","bus":"pci.1","addr":"0x0"}' \
+-blockdev '{"driver":"host_device","filename":"/dev/HostVG/QEMUGuest1","node-name":"libvirt-1-storage","read-only":false}' \
+-device '{"driver":"ide-hd","bus":"ide.0","drive":"libvirt-1-storage","id":"sata0-0-0","bootindex":1}' \
+-audiodev '{"id":"audio1","driver":"none"}' \
+-device '{"driver":"qxl-vga","id":"video0","max_outputs":1,"ram_size":67108864,"vram_size":33554432,"vram64_size_mb":0,"vgamem_mb":8,"bus":"pcie.0","addr":"0x1"}' \
+-global ICH9-LPC.noreboot=off \
+-watchdog-action reset \
+-object '{"qom-type":"iommufd","id":"iommufd0","fd":"20"}' \
+-device '{"driver":"vfio-pci","id":"hostdev0","iommufd":"iommufd0","fd":"0","bus":"pcie.0","addr":"0x3"}' \
+-sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \
+-msg timestamp=on
diff --git a/tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.xml b/tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.xml
new file mode 100644
index 0000000000..a6be49cbb3
--- /dev/null
+++ b/tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.xml
@@ -0,0 +1,60 @@
+<domain type='qemu'>
+  <name>q35-test</name>
+  <uuid>11dbdcdd-4c3b-482b-8903-9bdb8c0a2774</uuid>
+  <memory unit='KiB'>2097152</memory>
+  <currentMemory unit='KiB'>2097152</currentMemory>
+  <vcpu placement='static' cpuset='0-1'>2</vcpu>
+  <iommufd enabled='yes' fdgroup='iommu'/>
+  <os>
+    <type arch='x86_64' machine='q35'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <cpu mode='custom' match='exact' check='none'>
+    <model fallback='forbid'>qemu64</model>
+  </cpu>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-x86_64</emulator>
+    <disk type='block' device='disk'>
+      <driver name='qemu' type='raw'/>
+      <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='pcie-root-port'>
+      <model name='pcie-root-port'/>
+      <target chassis='1' port='0x10'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0' multifunction='on'/>
+    </controller>
+    <controller type='pci' index='2' model='pcie-root-port'>
+      <model name='pcie-root-port'/>
+      <target chassis='2' port='0x11'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x1'/>
+    </controller>
+    <controller type='sata' index='0'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
+    </controller>
+    <controller type='usb' index='0' model='qemu-xhci'>
+      <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
+    </controller>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <audio id='1' type='none'/>
+    <video>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1' primary='yes'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
+    </video>
+    <hostdev mode='subsystem' type='pci' managed='yes'>
+      <source>
+        <address domain='0x0000' bus='0x06' slot='0x12' function='0x5'/>
+      </source>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
+    </hostdev>
+    <watchdog model='itco' action='reset'/>
+    <memballoon model='none'/>
+  </devices>
+</domain>
diff --git a/tests/qemuxmlconfdata/iommufd-q35-fd.xml b/tests/qemuxmlconfdata/iommufd-q35-fd.xml
new file mode 100644
index 0000000000..1cef31fffa
--- /dev/null
+++ b/tests/qemuxmlconfdata/iommufd-q35-fd.xml
@@ -0,0 +1,38 @@
+<domain type='qemu'>
+  <name>q35-test</name>
+  <uuid>11dbdcdd-4c3b-482b-8903-9bdb8c0a2774</uuid>
+  <memory unit='KiB'>2097152</memory>
+  <currentMemory unit='KiB'>2097152</currentMemory>
+  <vcpu placement='static' cpuset='0-1'>2</vcpu>
+  <iommufd enabled='yes' fdgroup='iommu'/>
+  <os>
+    <type arch='x86_64' machine='q35'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-x86_64</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'/>
+    <hostdev mode='subsystem' type='pci' managed='yes'>
+      <source>
+        <address domain='0x0000' bus='0x06' slot='0x12' function='0x5'/>
+      </source>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
+    </hostdev>
+    <controller type='sata' index='0'/>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <video>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
+    </video>
+    <memballoon model='none'/>
+  </devices>
+</domain>
diff --git a/tests/qemuxmlconftest.c b/tests/qemuxmlconftest.c
index 32eb42dd19..3b0c212577 100644
--- a/tests/qemuxmlconftest.c
+++ b/tests/qemuxmlconftest.c
@@ -28,6 +28,9 @@
 #define LIBVIRT_QEMU_CAPSPRIV_H_ALLOW
 #include "qemu/qemu_capspriv.h"
 
+#define LIBVIRT_QEMU_PROCESSPRIV_H_ALLOW
+#include "qemu/qemu_processpriv.h"
+
 #include "testutilsqemu.h"
 
 #define VIR_FROM_THIS VIR_FROM_QEMU
@@ -98,7 +101,9 @@ testQemuPrepareHostdev(virDomainObj *vm)
         }
     }
 
-    if (virDomainDefHasPCIHostdevWithIOMMUFD(vm->def)) {
+    if (vm->def->iommufd_fdgroup) {
+        ignore_value(qemuProcessPrepareIommuFd(vm));
+    } else if (virDomainDefHasPCIHostdevWithIOMMUFD(vm->def)) {
         int iommufd = 0;
         priv->iommufd = qemuFDPassDirectNew("iommufd", &iommufd);
     }
@@ -2815,6 +2820,8 @@ mymain(void)
 
     DO_TEST_CAPS_LATEST("iommufd");
     DO_TEST_CAPS_LATEST("iommufd-q35");
+    DO_TEST_CAPS_ARCH_LATEST_FULL("iommufd-q35-fd", "x86_64",
+                                  ARG_FD_GROUP, "iommu", false, 1, 20);
     DO_TEST_CAPS_ARCH_LATEST("iommufd-virt", "aarch64");
     DO_TEST_CAPS_ARCH_LATEST("iommufd-virt-pci-bus-single", "aarch64");
 
-- 
2.53.0

On Thu, Mar 19, 2026 at 17:36:57 +0100, Pavel Hrdina via Devel wrote:
> From: Pavel Hrdina <phrdina@redhat.com>
> 
> Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
> ---
>  src/qemu/qemu_process.c                       | 12 ++--
>  src/qemu/qemu_processpriv.h                   |  2 +
>  .../iommufd-q35-fd.x86_64-latest.args         | 41 +++++++++++++
>  .../iommufd-q35-fd.x86_64-latest.xml          | 60 +++++++++++++++++++
>  tests/qemuxmlconfdata/iommufd-q35-fd.xml      | 38 ++++++++++++
>  tests/qemuxmlconftest.c                       |  9 ++-
>  6 files changed, 157 insertions(+), 5 deletions(-)
>  create mode 100644 tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.args
>  create mode 100644 tests/qemuxmlconfdata/iommufd-q35-fd.x86_64-latest.xml
>  create mode 100644 tests/qemuxmlconfdata/iommufd-q35-fd.xml
> 
> diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
> index c78fb4273c..14bc88b5cc 100644
> --- a/src/qemu/qemu_process.c
> +++ b/src/qemu/qemu_process.c
> @@ -7751,7 +7751,7 @@ qemuProcessOpenIommuFd(virDomainObj *vm)
>   *
>   * Returns: 0 on success, -1 on failure
>   */
> -static int
> +int

Add a note that it's exported only for testing.


Reviewed-by: Peter Krempa <pkrempa@redhat.com>