July 2026 - Devel - libvirt List Archives

[PATCH 0/6] qemu: add poll-weight support for iothreads
by Jaehoon Kim 22 Jul '26

22 Jul '26

This series adds support for the QEMU iothread poll-weight property, which controls the weight of the most recent event interval in the adaptive polling duration calculation. The valid range is [0, 63]; a value of 0 lets QEMU use its default weight. The series is split by layer: 1) conf/schema support 2) qemu capability detection 3) qemu backend support + public API constants + xmlconf tests 4) virsh support + test driver + virshtest 5) docs: fix pre-existing typos in iothread poll element description 6) docs: formatdomain documentation for poll-weight The series was validated with: meson test -C build virschematest meson test -C build qemucapabilitiestest meson test -C build qemuxmlconftest meson test -C build virshtest meson test -C build genericxml2xmltest QEMU commits: 9fea80ddf0 qapi/iothread: introduce poll-weight parameter for aio-poll 9563d0b5e2 aio-poll: refine iothread polling using weighted handler intervals ed21d9d65c aio-poll: avoid unnecessary polling time computation Jaehoon Kim (6): conf: add iothread poll-weight XML support qemu: capabilities: add capability for iothread poll-weight qemu: support iothread poll-weight virsh: add support for iothread poll-weight docs: fix typos in iothread poll element description docs: formatdomain: document iothread poll-weight docs/formatdomain.rst | 14 +++-- docs/manpages/virsh.rst | 18 ++++-- include/libvirt/libvirt-domain.h | 26 +++++++++ src/conf/domain_conf.c | 14 ++++- src/conf/domain_conf.h | 2 + src/conf/schemas/domaincommon.rng | 7 +++ src/qemu/qemu_capabilities.c | 2 + src/qemu/qemu_capabilities.h | 1 + src/qemu/qemu_command.c | 18 +++++- src/qemu/qemu_driver.c | 38 ++++++++++++ src/qemu/qemu_monitor.h | 2 + src/qemu/qemu_monitor_json.c | 18 ++++++ src/qemu/qemu_validate.c | 10 +++- src/test/test_driver.c | 12 ++++ tests/genericxml2xmlindata/iothreadids.xml | 2 +- .../caps_11.1.0_aarch64.xml | 1 + .../caps_11.1.0_x86_64.xml | 1 + ...othreads-ids-poll-weight.x86_64-11.0.0.err | 1 + ...threads-ids-poll-weight.x86_64-latest.args | 40 +++++++++++++ ...othreads-ids-poll-weight.x86_64-latest.xml | 58 +++++++++++++++++++ .../iothreads-ids-poll-weight.xml | 58 +++++++++++++++++++ tests/qemuxmlconftest.c | 2 + tests/virshtestdata/iothreads.in | 2 + tests/virshtestdata/iothreads.out | 18 ++++++ tools/virsh-domain.c | 18 ++++++ 25 files changed, 367 insertions(+), 16 deletions(-) create mode 100644 tests/qemuxmlconfdata/iothreads-ids-poll-weight.x86_64-11.0.0.err create mode 100644 tests/qemuxmlconfdata/iothreads-ids-poll-weight.x86_64-latest.args create mode 100644 tests/qemuxmlconfdata/iothreads-ids-poll-weight.x86_64-latest.xml create mode 100644 tests/qemuxmlconfdata/iothreads-ids-poll-weight.xml -- 2.54.0

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[PATCH] vbox: fix memory leak in vboxStartMachine()
by Elizaveta Tereshkina 22 Jul '26

22 Jul '26

vboxStartMachine() allocates sdlDisplay via g_strdup() and doesn't free it. Add VIR_FREE. Fixes: 3f4f0ef47d (vbox: Fix starting domains) Signed-off-by: Elizaveta Tereshkina <teryoshkina.ea(a)gmail.com> --- src/vbox/vbox_common.c | 1 + 1 file changed, 1 insertion(+) diff --git a/src/vbox/vbox_common.c b/src/vbox/vbox_common.c index 65ae9cc651..a47183927d 100644 --- a/src/vbox/vbox_common.c +++ b/src/vbox/vbox_common.c @@ -2252,6 +2252,7 @@ vboxStartMachine(virDomainPtr dom, int maxDomID, IMachine *machine) VBOX_UTF8_TO_UTF16(displayutf8, &env); VIR_FREE(displayutf8); VIR_FREE(guiDisplay); + VIR_FREE(sdlDisplay); VBOX_UTF8_TO_UTF16(sessType, &sessionType); } else if (vrdpPresent) { -- 2.39.2

2 2

[PATCH for 11.1] crypto: deprecate the AF_ALG crypto backend
by Daniel P. Berrangé 22 Jul '26

22 Jul '26

Linux 7.1 has deprecated the AF_ALG crypto backend: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… And has documented it to be always slower than userspace crypto: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… as a result of dropping support for zero-copy and hardware accelerators: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… The main use case for the AF_ALG impl was to improve the performance of virtio-crypto with the cryptodev-backend-builtin driver. In practice this did not matter since 'cryptodev-backend-lkcf' can do offload to the kernel via the keyctl syscall, and 'cryptodev-vhost-user' can offload to an external process which can optionally integrate with hardware accelerators without kernel assistance. The AF_ALG backend has no user visible configuration options at runtime, it is unconditionally tried with any use of the cipher APIs. So it does not strictly have to go through the deprecation process, however, it is left available initially in case there was an unexpected use case that relies on it which may be faster with old kernels before the above Linux commits. Suggested-by: Thomas Huth <thuth(a)redhat.com> Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com> --- docs/about/deprecated.rst | 21 +++++++++++++++++++++ meson.build | 6 ++++++ 2 files changed, 27 insertions(+) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 0c656a968f..54b2662752 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -416,6 +416,27 @@ ABI is long-obsolete. We are therefore deprecating both OABI support and NWFPE emulation, and they will be removed in a future QEMU release. +Build features +-------------- + +Crypto AF_ALG backend +--------------------- + +The use of the AF_ALG backend for cryptography has been deprecated +with no replacement. + +The AF_ALG interface is deprecated by Linux 7.1 and all support +for hardware accelerators has been removed. It will thus always be +slower than userspace crypto due to the overhead of copying data +to kernel space. The GNUTLS, Nettle and GCrypt libraries supported +by QEMU all include a variety of hardware optimized crypto +implementations which should suffice for typical needs. + +For the virtio-crypto device, the 'cryptodev-backend-lkcf' backend +can offload some operations to the kernel via the keyctl syscall, +and the 'cryptodev-vhost-user' backend can offload the device +backend to an external process which can integrate with crypto +accelerators. Backwards compatibility ----------------------- diff --git a/meson.build b/meson.build index 164328ded8..02cbe6445a 100644 --- a/meson.build +++ b/meson.build @@ -5053,3 +5053,9 @@ if not actually_reloc and (host_os == 'windows' or get_option('relocatable')) message('QEMU will have to be installed under ' + get_option('prefix') + '.') message('Use --disable-relocatable to remove this warning.') endif + +if get_option('crypto_afalg').enabled() + warning('Use of the AF_ALG crypto backend is deprecated, ' + + 'since Linux 7.1 has deprecated the AF_ALG interface ' + + 'and removed its ability to use hardware accelerators.') +endif -- 2.55.0

3 4

[PATCH 0/4] qemu: auto-select win-dmp for Windows guest crash dumps
by Denis V. Lunev 22 Jul '26

22 Jul '26

Auto-triggered dumps (on_crash, watchdog) always use QEMU's elf default, which is not WinDbg-loadable for a Windows guest and cannot be reliably converted after the fact. This was proposed before as a per-domain XML knob (https://www.mail-archive.com/devel@lists.libvirt.org/msg09638.html) Daniel P. Berrange objected: QEMU's query-dump-guest-memory-capability reported win-dmp as available on any x86-64 guest regardless of whether it had actually published a Windows dump header, so trusting it was not safe. QEMU's win_dump_available() has since been fixed to check the guest's vmcoreinfo note (https://lore.kernel.org/qemu-devel/20260619101834.228432-1-den@openvz.org/, commit b4bdad7dce). Patch 1 queries it directly instead of adding an XML knob. Patch 4 adds a quota (auto_dump_max_size): a guest that keeps crashing otherwise fills auto_dump_path one dump at a time. Oldest dumps are pruned after each new one; the dump just written is never removed, even alone over quota. Patches 2-3 give that setting and virtlogd's max_size a "10GiB"-style syntax instead of a raw byte count, reusing virScaleInteger()'s existing unit table. Validated against real guests: a Windows Server 2022 guest crashed via Sysinternals NotMyFault produces a PAGEDU64 (win-dmp) dump; an AlmaLinux 9 guest crashed via sysrq produces an ELF one. A 1GiB quota across two Linux crashes pruned the older dump and kept the newer, over-quota one. syntax-check and virstringtest pass. Denis V. Lunev (4): qemu: auto-select win-dmp for crash- and watchdog-triggered dumps util: add virStrToBytes() and virConfGetValueBytes() for scaled sizes logging: accept a unit suffix in virtlogd's max_size qemu: cap total size of auto-triggered dumps under auto_dump_path src/libvirt_private.syms | 2 + src/logging/log_daemon_config.c | 2 +- src/logging/log_daemon_config.h | 2 +- src/logging/virtlogd.conf | 7 +- src/qemu/qemu.conf.in | 16 ++++ src/qemu/qemu_conf.c | 2 + src/qemu/qemu_conf.h | 1 + src/qemu/qemu_driver.c | 127 +++++++++++++++++++++++++++++++- src/util/virconf.c | 47 ++++++++++++ src/util/virconf.h | 3 + src/util/virutil.c | 23 ++++++ src/util/virutil.h | 5 ++ tests/virstringtest.c | 76 +++++++++++++++++++ 13 files changed, 308 insertions(+), 5 deletions(-) -- 2.53.0

3 8

[PATCH 1/1] remote: fix stale status snapshot in daemonStreamHandleWrite
by Denis V. Lunev 22 Jul '26

22 Jul '26

daemonStreamHandleWrite() snapshots status from msg->header.status before dispatching to the per-type handler, then reuses that stale snapshot afterwards to decide whether to send a fake release reply. A stale snapshot lets it send that reply twice for the same 'msg', linking the message to itself and deadlooping the event loop thread in virNetMessageQueuePush()'s tail-walk loop. Remove the 'status' variable and read msg->header.status directly at the point of use instead. Commit 411cbe7199c ("remote: fix stream use-after-free") introduced it alongside its real fix: it also moved virNetMessageQueueServe() to dequeue 'msg' from stream->rx before dispatch instead of after, which is what actually prevents corrupting stream->rx's linkage and remains unchanged here. The variable itself was never load-bearing: no dispatch handler frees 'msg' on the path that reaches this check, so reading msg->header.status straight from 'msg' cannot go stale. Fixes: 411cbe7199ce ("remote: fix stream use-after-free") Signed-off-by: Denis V. Lunev <den(a)openvz.org> --- src/remote/remote_daemon_stream.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/src/remote/remote_daemon_stream.c b/src/remote/remote_daemon_stream.c index 3777c8e684..437cec374f 100644 --- a/src/remote/remote_daemon_stream.c +++ b/src/remote/remote_daemon_stream.c @@ -736,7 +736,6 @@ static int daemonStreamHandleWrite(virNetServerClient *client, daemonClientStream *stream) { - virNetMessageStatus status = VIR_NET_OK; VIR_DEBUG("client=%p, stream=%p", client, stream); while (stream->rx && !stream->closed) { @@ -748,10 +747,8 @@ daemonStreamHandleWrite(virNetServerClient *client, * Otherwise just carry on with processing stream * data. */ ret = daemonStreamHandleHole(client, stream, msg); - status = msg->header.status; } else if (msg->header.type == VIR_NET_STREAM) { - status = msg->header.status; - switch (status) { + switch (msg->header.status) { case VIR_NET_OK: ret = daemonStreamHandleFinish(client, stream, msg); break; @@ -791,7 +788,7 @@ daemonStreamHandleWrite(virNetServerClient *client, * onto the wire, but this causes the client to reset * its active request count / throttling */ - if (status == VIR_NET_CONTINUE) { + if (msg->header.status == VIR_NET_CONTINUE) { virNetMessageClear(msg); msg->header.type = VIR_NET_REPLY; if (virNetServerClientSendMessage(client, msg) < 0) { -- 2.53.0

1 0

[libvirt-python] RFC: Adding Sphinx API documentation for Python bindings
by Radoslaw Smigielski 22 Jul '26

22 Jul '26

Hi, I'd like to propose adding generated API documentation for the libvirt-python bindings and would appreciate the community's opinion on whether this is worthwhile. The problem: The libvirt-python bindings currently have no browsable API documentation. Users who want to discover available methods, their parameters, or behavior have to either read the C API docs and map them to Python or inspect the generated libvirt.py source directly, or rely on IDE auto-completion. But in the same time the infrastructure to produce good documentation is already in place, I mean XML API descriptions libvirt-api.xml, generator.py and override files (libvirt-override-virDomain.py, etc.) also contain docstrings. These docstrings are present but are not rendered anywhere for users to browse. The proposal: Add a minimal Sphinx setup (docs/conf.py, a few .rst files, and a requirements-docs.txt) to generate HTML API reference from the existing docstrings. This would cover all four modules: libvirt, libvirt_qemu, libvirt_lxc, and libvirtaio. This is a working prototype that builds successfully and produces complete API reference pages. https://gitlab.com/rsmigiel/libvirt-python/-/commit/53b1fdeca932de7b8deffb2… Would this be a welcome change? Any concerns or suggestions on the approach? Thanks for your feedback! ---------------------- < Tℏanks | Radek >

1 0

[PATCH 0/4] API docs fixes
by Peter Krempa 21 Jul '26

21 Jul '26

Peter Krempa (4): libvirt-domain: Use consistent flag names for APIs declaring use of 'virDomainDeviceModifyFlags' libvirt-qemu: Add reference to QMP protocol documentation libvirt-qemu: Document that 'virDomainQemuAttach' no longer works libvirt-qemu: Add reference to QEMU agent protocol syntax src/libvirt-domain.c | 24 ++++++++++++------------ src/libvirt-qemu.c | 17 ++++++++++++++++- 2 files changed, 28 insertions(+), 13 deletions(-) -- 2.55.0

2 5

[PATCH v19 03/15] net/tap: deprecate "no" as special value for script/downscript
by Vladimir Sementsov-Ogievskiy 21 Jul '26

21 Jul '26

The interface is ambiguous, as "no" is valid file name. So, using "no" as a special value to disable script is deprecated. Use an empty string ("script=" / "downscript=") instead. In a future version, "no" will be treated as a plain file name, just like any other non-empty value. Document the deprecation in docs/about/deprecated.rst, qapi/net.json, and qemu-options.hx. Update other docs to use empty string instead of "no". Add a warning. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov(a)yandex-team.ru> --- docs/about/deprecated.rst | 18 ++++++++++++++ docs/system/i386/microvm.rst | 4 +-- docs/system/i386/xenpvh.rst | 2 +- docs/system/ppc/ppce500.rst | 4 +-- docs/system/riscv/microchip-icicle-kit.rst | 2 +- docs/system/riscv/sifive_u.rst | 2 +- net/tap.c | 29 ++++++++++++++-------- qapi/net.json | 12 ++++++--- qemu-options.hx | 7 ++++-- 9 files changed, 56 insertions(+), 24 deletions(-) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 0c656a968fc..c4929317e3a 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -71,6 +71,15 @@ flexible enough. The monitor objects have been converted to QOM, so ``-mon mode=control`` is replaced by ``-object monitor-qmp``. The short convenience options are not deprecated, only ``-mon``. +``script=no`` and ``downscript=no`` for ``-netdev tap`` (since 11.2) +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' + +The special value ``"no"`` for the ``script`` and ``downscript`` +parameters of ``-netdev tap`` disables script execution. This special +treatment of ``"no"`` is deprecated. Use an empty string (``script=`` +or ``downscript=``) to disable script execution instead. In a future +version, ``"no"`` will be treated as a plain file name. + QEMU Machine Protocol (QMP) commands ------------------------------------ @@ -164,6 +173,15 @@ Use ``job-finalize`` instead. Use ``query-accelerators`` instead. +``"no"`` as value of ``script``/``downscript`` for tap in ``netdev_add`` (since 11.2) +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' + +The special value ``"no"`` for the ``script`` and ``downscript`` +parameters of ``netdev_add`` with ``type=tap`` disables script +execution. This special treatment of ``"no"`` is deprecated. Use an +empty string instead. In a future version, ``"no"`` will be treated as +a plain file name. + Human Machine Protocol (HMP) commands ------------------------------------- diff --git a/docs/system/i386/microvm.rst b/docs/system/i386/microvm.rst index 1675e37d3e7..077ea15751e 100644 --- a/docs/system/i386/microvm.rst +++ b/docs/system/i386/microvm.rst @@ -79,7 +79,7 @@ legacy ``ISA serial`` device as console:: -serial stdio \ -drive id=test,file=test.img,format=raw,if=none \ -device virtio-blk-device,drive=test \ - -netdev tap,id=tap0,script=no,downscript=no \ + -netdev tap,id=tap0,script=,downscript= \ -device virtio-net-device,netdev=tap0 While the example above works, you might be interested in reducing the @@ -103,7 +103,7 @@ disabled:: -device virtconsole,chardev=virtiocon0 \ -drive id=test,file=test.img,format=raw,if=none \ -device virtio-blk-device,drive=test \ - -netdev tap,id=tap0,script=no,downscript=no \ + -netdev tap,id=tap0,script=,downscript= \ -device virtio-net-device,netdev=tap0 diff --git a/docs/system/i386/xenpvh.rst b/docs/system/i386/xenpvh.rst index 904778e3f5c..862f38830b1 100644 --- a/docs/system/i386/xenpvh.rst +++ b/docs/system/i386/xenpvh.rst @@ -42,7 +42,7 @@ case you need to construct one manually: -vnc none \ -display none \ -device virtio-net-pci,id=nic0,netdev=net0,mac=00:16:3e:5c:81:78 \ - -netdev type=tap,id=net0,ifname=vif3.0-emu,br=xenbr0,script=no,downscript=no \ + -netdev type=tap,id=net0,ifname=vif3.0-emu,br=xenbr0,script=,downscript= \ -smp 4,maxcpus=4 \ -nographic \ -machine xenpvh,ram-low-base=0,ram-low-size=2147483648,ram-high-base=4294967296,ram-high-size=2147483648,pci-ecam-base=824633720832,pci-ecam-size=268435456,pci-mmio-base=4026531840,pci-mmio-size=33554432,pci-mmio-high-base=824902156288,pci-mmio-high-size=68719476736 \ diff --git a/docs/system/ppc/ppce500.rst b/docs/system/ppc/ppce500.rst index c9fe0915dc5..ec5aaf14fd9 100644 --- a/docs/system/ppc/ppce500.rst +++ b/docs/system/ppc/ppce500.rst @@ -158,14 +158,14 @@ interface at PCI address 0.1.0, but we can switch that to an e1000 NIC by: $ qemu-system-ppc64 -M ppce500 -smp 4 -m 2G \ -display none -serial stdio \ -bios u-boot \ - -nic tap,ifname=tap0,script=no,downscript=no,model=e1000 + -nic tap,ifname=tap0,script=,downscript=,model=e1000 The QEMU ``ppce500`` machine can also dynamically instantiate an eTSEC device if “-device eTSEC” is given to QEMU: .. code-block:: bash - -netdev tap,ifname=tap0,script=no,downscript=no,id=net0 -device eTSEC,netdev=net0 + -netdev tap,ifname=tap0,script=,downscript=,id=net0 -device eTSEC,netdev=net0 Root file system on flash drive ------------------------------- diff --git a/docs/system/riscv/microchip-icicle-kit.rst b/docs/system/riscv/microchip-icicle-kit.rst index 9809e94b84b..7fdb96601ad 100644 --- a/docs/system/riscv/microchip-icicle-kit.rst +++ b/docs/system/riscv/microchip-icicle-kit.rst @@ -84,7 +84,7 @@ Then we can boot the machine by: $ qemu-system-riscv64 -M microchip-icicle-kit -smp 5 -m 2G \ -sd path/to/sdcard.img \ -nic user,model=cadence_gem \ - -nic tap,ifname=tap,model=cadence_gem,script=no \ + -nic tap,ifname=tap,model=cadence_gem,script= \ -display none -serial stdio \ -kernel path/to/u-boot/build/dir/u-boot.bin \ -dtb path/to/u-boot/build/dir/u-boot.dtb diff --git a/docs/system/riscv/sifive_u.rst b/docs/system/riscv/sifive_u.rst index 8f55ae8e313..0e4dcf3e70c 100644 --- a/docs/system/riscv/sifive_u.rst +++ b/docs/system/riscv/sifive_u.rst @@ -199,7 +199,7 @@ To boot the VxWorks kernel in QEMU with the ``sifive_u`` machine, use: $ qemu-system-riscv64 -M sifive_u -smp 5 -m 2G \ -display none -serial stdio \ - -nic tap,ifname=tap0,script=no,downscript=no \ + -nic tap,ifname=tap0,script=,downscript= \ -kernel /path/to/vxWorks \ -append "gem(0,0)host:vxWorks h=192.168.200.1 e=192.168.200.2:ffffff00 u=target pw=vxTarget f=0x01" diff --git a/net/tap.c b/net/tap.c index fedd48c48d2..2e94b4015f6 100644 --- a/net/tap.c +++ b/net/tap.c @@ -92,34 +92,40 @@ static void launch_script(const char *setup_script, const char *ifname, static void tap_send(void *opaque); static void tap_writable(void *opaque); -static bool tap_is_explicit_no_script(const char *script_arg) +static bool tap_is_explicit_no_script(const char *script_arg_name, + const char *script_arg_value) { - if (!script_arg) { + if (!script_arg_value) { return false; } - if (script_arg[0] == '\0') { + if (script_arg_value[0] == '\0') { return true; } - if (strcmp(script_arg, "no") == 0) { + if (strcmp(script_arg_value, "no") == 0) { + warn_report("%s=no is deprecated; use %s= instead " + "(empty string instead of 'no')", + script_arg_name, script_arg_name); return true; } return false; } -static char *tap_parse_script(const char *script_arg, const char *default_path) +static char *tap_parse_script(const char *script_arg_name, + const char *script_arg_value, + const char *default_path) { - if (tap_is_explicit_no_script(script_arg)) { + if (tap_is_explicit_no_script(script_arg_name, script_arg_value)) { return NULL; } - if (!script_arg) { + if (!script_arg_value) { return get_relocated_path(default_path); } - return g_strdup(script_arg); + return g_strdup(script_arg_value); } static void tap_update_fd_handler(TAPState *s) @@ -740,7 +746,7 @@ static bool net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, qemu_set_info_str(&s->nc, "helper=%s", tap->helper); } else { qemu_set_info_str(&s->nc, "ifname=%s,script=%s,downscript=%s", ifname, - script ?: "no", downscript ?: "no"); + script ?: "", downscript ?: ""); if (downscript) { snprintf(s->down_script, sizeof(s->down_script), "%s", downscript); @@ -946,9 +952,10 @@ int net_init_tap(const Netdev *netdev, const char *name, } } else { g_autofree char *script = - tap_parse_script(tap->script, DEFAULT_NETWORK_SCRIPT); + tap_parse_script("script", tap->script, DEFAULT_NETWORK_SCRIPT); g_autofree char *downscript = - tap_parse_script(tap->downscript, DEFAULT_NETWORK_DOWN_SCRIPT); + tap_parse_script("downscript", tap->downscript, + DEFAULT_NETWORK_DOWN_SCRIPT); if (tap->ifname) { pstrcpy(ifname, sizeof ifname, tap->ifname); diff --git a/qapi/net.json b/qapi/net.json index 8f0915c4d86..ada0329ef9d 100644 --- a/qapi/net.json +++ b/qapi/net.json @@ -399,15 +399,19 @@ # @fds: multiple file descriptors of already opened multiqueue capable # tap # -# @script: script to initialize the interface. An empty string or -# "no" disables script execution. Defaults to +# @script: script to initialize the interface. An empty string +# disables script execution. Defaults to # ``<sysconfdir>/qemu-ifup``, where ``<sysconfdir>`` is the # system configuration directory at build time (typically /etc). +# Using "no" to disable script execution is deprecated (since +# 11.2); use an empty string instead. # -# @downscript: script to shut down the interface. An empty string or -# "no" disables script execution. Defaults to +# @downscript: script to shut down the interface. An empty string +# disables script execution. Defaults to # ``<sysconfdir>/qemu-ifdown``, where ``<sysconfdir>`` is the # system configuration directory at build time (typically /etc). +# Using "no" to disable script execution is deprecated (since +# 11.2); use an empty string instead. # # @br: bridge name (since 2.8) # diff --git a/qemu-options.hx b/qemu-options.hx index 200949655ea..7b9a14f5b38 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -3014,7 +3014,8 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" " to deconfigure it\n" - " use '[down]script=no' or '[down]script=' to disable script execution\n" + " use '[down]script=' to disable script execution\n" + " ('[down]script=no' is deprecated and will be treated as a file name in future)\n" " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" " configure it\n" " use 'fd=h' to connect to an already opened TAP interface\n" @@ -3553,7 +3554,9 @@ SRST ``<sysconfdir>/qemu-ifup`` and the default network deconfigure script is ``<sysconfdir>/qemu-ifdown``, where ``<sysconfdir>`` is the system configuration directory at build time (typically ``/etc``). - Use ``[down]script=no`` or ``[down]script=`` to disable script execution. + Use ``[down]script=`` to disable script execution. + Using ``[down]script=no`` is deprecated; in a future version it will + be treated as a plain file name. If running QEMU as an unprivileged user, use the network helper to configure the TAP interface and attach it to the bridge. -- 2.43.0

2 1

Plans for 12.6.0 release (freeze on 2026-07-27)
by Jiri Denemark 20 Jul '26

20 Jul '26

We are getting close to 12.6.0 release of libvirt. To aim for the release on Monday 03 Aug I suggest entering the freeze on Monday 27 Jul and tagging RC2 on Thursday 30 Jul. I hope this works for everyone. Jirka

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[PATCH 0/2] qemu: Fix detach of a CD-ROM device with no media
by Mitsuru Kariya 20 Jul '26

20 Jul '26

Detaching a CD-ROM device that has no media inserted currently logs an internal error: internal error: unable to execute QEMU command 'blockdev-del': Failed to find node with node-name='libvirt-N-storage' or, when no stale node name is present in the source: internal error: argument key 'node-name' must not have null value The root cause is that an empty disk source (path == NULL) satisfies virStorageSourceIsBacking() while no corresponding blockdev node ever exists in QEMU, so the detach path prepares a blockdev-del for a node that was never created. Patch 1 fixes the detach path itself: qemuDomainRemoveDiskDevice() now skips the blockdev detach preparation for an empty source, mirroring what the old-media detach in qemuDomainChangeMediaBlockdev() already does. Patch 2 fixes the way the stale node name gets there in the first place: qemuDomainChangeEjectableMedia() ran the full image setup (qemuDomainPrepareDiskSource(), backing chain detection, storage access, managed PR) even when ejecting to no media, assigning node names to an empty source that are never realized in QEMU. The setup is now skipped for an empty source, mirroring qemuDomainAttachDeviceDiskLiveInternal(), and rollback only revokes storage access when it was actually granted. To reproduce the 1st message: 1. Start a domain with a CD-ROM device with media attached 2. virsh change-media $dom $target --eject --live 3. virsh detach-disk $dom $target --live To reproduce the 2nd message: 1. Start a domain with a CD-ROM device without media attached 2. virsh detach-disk $dom $target --live No regression tests are added. Neither failure mode is reachable from qemuhotplugtest: the "null value" variant fails while constructing the blockdev-del arguments, before any QMP command is sent, leaving nothing for the test monitor to observe; the stale-node-name variant does emit a blockdev-del and would be detectable, but requires a preceding media eject to set up, which qemuhotplugtest cannot drive. Mitsuru Kariya (2): qemu: Skip empty disk source when detaching a disk device qemu: Don't prepare an empty disk source on media change src/qemu/qemu_hotplug.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) base-commit: 674fcf87bdd479302032fbeb331fea2aa51606ac -- 2.43.0

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