Package: virtiofsd
Version: 1.14.0-2
Severity: important
Dear Maintainer,
After upgrading from 1.14.0-1 which works fine, to 1.14.0-2, I can now
not mount any virtiofs shares on Sid (tried on 2 different Trixie guests).
Error from virt-manager:
Error starting domain: internal error: QEMU unexpectedly closed the monitor
(vm='debian13'): 2026-08-11T10:15:39.842604Z qemu-system-x86_64: -device
{"driver":"vhost-user-fs-pci","id":"fs0","chardev":"chr-vu-
fs0","tag":"kernel","bus":"pci.2","addr":"0x0"}: Failed to read msg header.
Read 0 instead of 12. Original request 0.
2026-08-11T10:15:39.842685Z qemu-system-x86_64: -device
{"driver":"vhost-user-
fs-pci","id":"fs0","chardev":"chr-vu-
fs0","tag":"kernel","bus":"pci.2","addr":"0x0"}: vhost_backend_init failed:
Protocol error
Traceback (most recent call last):
File "/usr/share/virt-manager/virtManager/asyncjob.py", line 67, in
cb_wrapper
callback(asyncjob, *args, **kwargs)
~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/share/virt-manager/virtManager/asyncjob.py", line 101, in
tmpcb
callback(*args, **kwargs)
~~~~~~~~^^^^^^^^^^^^^^^^^
File "/usr/share/virt-manager/virtManager/object/libvirtobject.py",
line 57,
in newfn
ret = fn(self, *args, **kwargs)
File "/usr/share/virt-manager/virtManager/object/domain.py", line
1446, in
startup
self._backend.create()
~~~~~~~~~~~~~~~~~~~~^^
File "/usr/lib/python3/dist-packages/libvirt.py", line 1401, in create
raise libvirtError('virDomainCreate() failed')
libvirt.libvirtError: internal error: QEMU unexpectedly closed the monitor
(vm='debian13'): 2026-08-11T10:15:39.842604Z qemu-system-x86_64: -device
{"driver":"vhost-user-fs-pci","id":"fs0","chardev":"chr-vu-
fs0","tag":"kernel","bus":"pci.2","addr":"0x0"}: Failed to read msg header.
Read 0 instead of 12. Original request 0.
2026-08-11T10:15:39.842685Z qemu-system-x86_64: -device
{"driver":"vhost-user-
fs-pci","id":"fs0","chardev":"chr-vu-
fs0","tag":"kernel","bus":"pci.2","addr":"0x0"}: vhost_backend_init failed:
Protocol error
Or on the CLI:
$ virsh attach-device debian13 virtiofs-kernel.xml --live
error: Failed to attach device from virtiofs-kernel.xml
error: internal error: unable to execute QEMU command 'device_add':
vhost_backend_init failed: Protocol error
Here's my virtiofs-kernel.xml:
<filesystem type="mount" accessmode="passthrough">
<driver type="virtiofs"/>
<binary path="/usr/libexec/virtiofsd"/>
<idmap>
<uid start="502" target="502" count="1"/>
<gid start="502" target="502" count="1"/>
</idmap>
<source dir="/home/simon/kernel"/>
<target dir="kernel"/>
</filesystem>
I've not changed anything else and downgrading to 1.14.0-1 works fine again.
-- System Information:
Debian Release: forky/sid
APT prefers unstable
APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)
Kernel: Linux 7.1.7+deb14-amd64 (SMP w/32 CPU threads; PREEMPT)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8),
LANGUAGE=en_GB:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
Versions of packages virtiofsd depends on:
ii libc6 2.43-3
ii libcap-ng0 0.9.3-1+b1
ii libgcc-s1 16.2.0-1
ii libseccomp2 2.6.1-1
ii uidmap 1:4.19.3-2
virtiofsd recommends no packages.
virtiofsd suggests no packages.
-- no debconf information
--
Simon John
