qemu_hotplug: enter monitor in order to rollback passed FD

[libvirt PATCH] qemu_hotplug: enter monitor in order to rollback passed FD

Posted by Pavel Hrdina via Devel 4 days, 15 hours ago

From: Pavel Hrdina <phrdina@redhat.com>

Reported-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
---
 src/qemu/qemu_hotplug.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index bede4e3ccd..93cbaf1d91 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -1680,8 +1680,10 @@ qemuDomainAttachHostPCIDevice(virQEMUDriver *driver,
         qemuDomainObjExitMonitor(vm);
     }
 
+    qemuDomainObjEnterMonitor(vm);
     qemuFDPassDirectTransferMonitorRollback(hostdevPriv->vfioDeviceFd, priv->mon);
     qemuFDPassDirectTransferMonitorRollback(priv->iommufd, priv->mon);
+    qemuDomainObjExitMonitor(vm);
 
     if (releaseaddr)
         qemuDomainReleaseDeviceAddress(vm, info);
-- 
2.53.0

Re: [libvirt PATCH] qemu_hotplug: enter monitor in order to rollback passed FD

Posted by Jiri Denemark via Devel 4 days, 14 hours ago

On Thu, Feb 26, 2026 at 10:59:57 +0100, Pavel Hrdina wrote:
> From: Pavel Hrdina <phrdina@redhat.com>
> 
> Reported-by: Peter Krempa <pkrempa@redhat.com>
> Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
> ---
>  src/qemu/qemu_hotplug.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
> index bede4e3ccd..93cbaf1d91 100644
> --- a/src/qemu/qemu_hotplug.c
> +++ b/src/qemu/qemu_hotplug.c
> @@ -1680,8 +1680,10 @@ qemuDomainAttachHostPCIDevice(virQEMUDriver *driver,
>          qemuDomainObjExitMonitor(vm);
>      }
>  
> +    qemuDomainObjEnterMonitor(vm);
>      qemuFDPassDirectTransferMonitorRollback(hostdevPriv->vfioDeviceFd, priv->mon);
>      qemuFDPassDirectTransferMonitorRollback(priv->iommufd, priv->mon);
> +    qemuDomainObjExitMonitor(vm);
>  
>      if (releaseaddr)
>          qemuDomainReleaseDeviceAddress(vm, info);

Reviewed-by: Jiri Denemark <jdenemar@redhat.com>

Re: [libvirt PATCH] qemu_hotplug: enter monitor in order to rollback passed FD

Posted by Peter Krempa via Devel 4 days, 14 hours ago

On Thu, Feb 26, 2026 at 10:59:57 +0100, Pavel Hrdina via Devel wrote:
> From: Pavel Hrdina <phrdina@redhat.com>
> 
> Reported-by: Peter Krempa <pkrempa@redhat.com>
> Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
> ---
>  src/qemu/qemu_hotplug.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
> index bede4e3ccd..93cbaf1d91 100644
> --- a/src/qemu/qemu_hotplug.c
> +++ b/src/qemu/qemu_hotplug.c
> @@ -1680,8 +1680,10 @@ qemuDomainAttachHostPCIDevice(virQEMUDriver *driver,
>          qemuDomainObjExitMonitor(vm);
>      }
>  
> +    qemuDomainObjEnterMonitor(vm);

Ideally move ^^^ above the 'if (removeiommufd)' clause above and remove
the monitor scope from that block.


>      qemuFDPassDirectTransferMonitorRollback(hostdevPriv->vfioDeviceFd, priv->mon);
>      qemuFDPassDirectTransferMonitorRollback(priv->iommufd, priv->mon);
> +    qemuDomainObjExitMonitor(vm);


With tthe above change:

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