The colo-compare option documentation has some formatting issues: it
uses a "@var{...}" syntax which is not used elsewhere and which is
rendered literally into the HTML documentation. The bare "@" sign
also results in an unintended 'mailto:' hyperlink.
Rewrite this into the style we seem to use most in the rest of
the command line options, where an option which takes an argument
is written as "my-option=<thing>".
We take the opportunity to make the documentation a little clearer
by splitting up the long paragraph and using preformatted-text
markup for the names of the suboptions.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Zhang Chen <zhangckid@gmail.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20260115142629.665319-5-peter.maydell@linaro.org
A few entries in qemu-options.hx use the syntax "my-option=@var{name}"
(or @var{} with no name specified) when documenting an option that takes
an argument. This syntax isn't consistently used, and the documentation
generation has no support for it: it just appears literally in the
HTML output.
Switch these uses to the more common "my-option=<name>". This also
doesn't have any particular support in the documentation generation
and so appears literally in the output, but it is a little less odd
looking to the end-user.
The other common pattern we have is "my-option=name" with no marking
at all that the right hand side of the '=' is not literal text;
using <> seems preferable to me, as it makes it more distinct from
cases where the right hand side is documenting that only certain
values are permitted, as in "my-option=on|off". This patch doesn't
do anything about existing uses of this pattern (except in one case
which was so confused as to use "my-option=@var{}" in the --help
output and "my-option=" in the RST output, where we change both
for consistency), but prefers not to add more of them.
We don't change the uses of @var in the colo-compare documentation,
as that part deserves a slightly more wide-ranging overhaul that
is better in its own commit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Zhang Chen <zhangckid@gmail.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20260115142629.665319-4-peter.maydell@linaro.org
Libguestfs wants to use qemu to run a captive appliance. When the
program linked to libguestfs exits, we want qemu to be cleaned up.
Libguestfs goes to great lengths to do this at the moment: it either
forks a separate process to ensure clean-up is done, or it asks
libvirt to clean up the qemu process. However this is complicated and
not totally reliable.
On Linux, FreeBSD and macOS, there are mechanisms to ensure a signal
or message is delivered to a process when its parent process goes
away. The qemu test suite even uses this mechanism on Linux (see
PR_SET_PDEATHSIG in tests/qtest/libqtest.c).
In nbdkit we have long had the concept of running nbdkit captively,
and we have the nbdkit --exit-with-parent flag to help
(https://libguestfs.org/nbdkit-captive.1.html#EXIT-WITH-PARENT)
This commit adds the same mechanism. The syntax is:
qemu -run-with exit-with-parent=on [...]
This is not a feature that most typical users of qemu (for running
general purpose, long-lived VMs) should use, so it defaults to off.
The exit-with-parent.[ch] files are copied from nbdkit, where they
have a 3-clause BSD license which is compatible with qemu:
https://gitlab.com/nbdkit/nbdkit/-/tree/master/common/utils?ref_type=heads
Thanks: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
virtio,pci,pc: features, fixes
users can now control VM bit in smbios.
vhost-user-device is now user-createable.
intel_iommu now supports PRI
virtio-net now supports GSO over UDP tunnel
ghes now supports error injection
amd iommu now supports dma remapping for vfio
better error messages for virtio
small fixes all over the place.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (75 commits)
virtio: improve virtqueue mapping error messages
pci: Fix wrong parameter passing to pci_device_get_iommu_bus_devfn()
intel_iommu: Simplify caching mode check with VFIO device
intel_iommu: Enable Enhanced Set Root Table Pointer Support (ESRTPS)
vdpa-dev: add get_vhost() callback for vhost-vdpa device
amd_iommu: HATDis/HATS=11 support
intel-iommu: Move dma_translation to x86-iommu
amd_iommu: Refactor amdvi_page_walk() to use common code for page walk
amd_iommu: Do not assume passthrough translation when DTE[TV]=0
amd_iommu: Toggle address translation mode on devtab entry invalidation
amd_iommu: Add dma-remap property to AMD vIOMMU device
amd_iommu: Set all address spaces to use passthrough mode on reset
amd_iommu: Toggle memory regions based on address translation mode
amd_iommu: Invalidate address translations on INVALIDATE_IOMMU_ALL
amd_iommu: Add replay callback
amd_iommu: Unmap all address spaces under the AMD IOMMU on reset
amd_iommu: Use iova_tree records to determine large page size on UNMAP
amd_iommu: Sync shadow page tables on page invalidation
amd_iommu: Add basic structure to support IOMMU notifier updates
amd_iommu: Add a page walker to sync shadow page tables on invalidation
...
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Document the common parameters used when emulating AMD vIOMMU.
Besides the two amd-iommu specific options: 'xtsup' and 'dma-remap', the
the generic x86 IOMMU option 'intremap' is also included, since it is
typically specified in QEMU command line examples and mailing list threads.
Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20250919213515.917111-3-alejandro.j.jimenez@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch adds the ability to map a host unix socket to a guest tcp socket when
using the slirp backend. This feature was added in libslirp version 4.7.0.
A new syntax for unix socket: -hostfwd=unix:hostpath-[guestaddr]:guestport
Signed-off-by: Viktor Kurilko <murlockkinght@gmail.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Message-ID: <20250808143904.363907-1-murlockkinght@gmail.com>
This is useful to be able to freeze a specific version of SeaBIOS to
prevent guest visible changes between BIOS updates. This is currently
not possible since the extension byte 2 provided by SeaBIOS does not
set the VM bit, whereas QEMU sets it unconditionally.
Allowing to clear it also seems useful if we want to hide the fact that
the guest system is running inside a virtual machine.
Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20250724195409.43499-1-d-tatianin@yandex-team.ru>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
UI-related for 10.1
- [PATCH v3 0/2] ui/vnc: Do not copy z_stream
- [PATCH v6 0/7] ui/spice: Enable gl=on option for non-local or remote clients
- [PATCH v6 0/1] Allow injection of virtio-gpu EDID name
- [PATCH 0/2] ui/gtk: Add keep-aspect-ratio and scale option
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# gpg: Good signature from "Marc-André Lureau <marcandre.lureau@redhat.com>" [full]
# gpg: aka "Marc-André Lureau <marcandre.lureau@gmail.com>" [full]
# Primary key fingerprint: 87A9 BD93 3F87 C606 D276 F62D DAE8 E109 7596 9CE5
* tag 'ui-pull-request' of https://gitlab.com/marcandre.lureau/qemu:
tpm: "qemu -tpmdev help" should return success
ui/gtk: Add scale option
ui/gtk: Add keep-aspect-ratio option
hw/display: Allow injection of virtio-gpu EDID name
ui/spice: Blit the scanout texture if its memory layout is not linear
ui/spice: Create a new texture with linear layout when gl=on is specified
ui/console-gl: Add a helper to create a texture with linear memory layout
ui/spice: Add an option to submit gl_draw requests at fixed rate
ui/spice: Add an option for users to provide a preferred video codec
ui/spice: Enable gl=on option for non-local or remote clients
ui/egl-helpers: Error check the fds in egl_dmabuf_export_texture()
ui/vnc: Introduce the VncWorker type
ui/vnc: Do not copy z_stream
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
virtio,pci,pc: features, fixes, tests
SPCR acpi table can now be disabled
vhost-vdpa can now report hashing capability to guest
PPTT acpi table now tells guest vCPUs are identical
vost-user-blk now shuts down faster
loongarch64 now supports bios-tables-test
intel_iommu now supports ATS
cxl now supports DCD Fabric Management Command Set
arm now supports acpi pci hotplug
fixes, cleanups
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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# gpg: issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
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# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
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* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (97 commits)
hw/cxl: mailbox-utils: 0x5605 - FMAPI Initiate DC Release
hw/cxl: mailbox-utils: 0x5604 - FMAPI Initiate DC Add
hw/cxl: Create helper function to create DC Event Records from extents
hw/cxl: mailbox-utils: 0x5603 - FMAPI Get DC Region Extent Lists
hw/cxl: mailbox-utils: 0x5602 - FMAPI Set DC Region Config
hw/mem: cxl_type3: Add DC Region bitmap lock
hw/cxl: Move definition for dynamic_capacity_uuid and enum for DC event types to header
hw/cxl: mailbox-utils: 0x5601 - FMAPI Get Host Region Config
hw/mem: cxl_type3: Add dsmas_flags to CXLDCRegion struct
hw/cxl: mailbox-utils: 0x5600 - FMAPI Get DCD Info
hw/cxl: fix DC extent capacity tracking
tests: virt: Update expected ACPI tables for virt test
hw/acpi/aml-build: Build a root node in the PPTT table
hw/acpi/aml-build: Set identical implementation flag for PPTT processor nodes
tests: virt: Allow changes to PPTT test table
qtest/bios-tables-test: Generate reference blob for DSDT.acpipcihp
qtest/bios-tables-test: Generate reference blob for DSDT.hpoffacpiindex
tests/qtest/bios-tables-test: Add aarch64 ACPI PCI hotplug test
tests/qtest/bios-tables-test: Prepare for addition of acpi pci hp tests
hw/arm/virt: Let virt support pci hotplug/unplug GED event
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Conflicts:
net/vhost-vdpa.c
vhost_vdpa_set_steering_ebpf() was removed, resolve the context
conflict.
Extend 'inhibit=on' setting with the option to specify a pinned XSK map
path along with a starting index (default 0) to push the created XSK
sockets into. Example usage:
# ./build/qemu-system-x86_64 [...] \
-netdev af-xdp,ifname=enp2s0f0np0,id=net0,mode=native,queues=2,start-queue=14,inhibit=on,map-path=/sys/fs/bpf/xsks_map,map-start-index=14 \
-device virtio-net-pci,netdev=net0 [...]
This is useful for the case where an existing XDP program with XSK map
is present on the AF_XDP supported phys device and the XSK map is not
yet populated. For example, the former could have been pre-loaded onto
the netdevice by a control plane, which later launches QEMU to populate
it with XSK sockets.
Normally, the main idea behind 'inhibit=on' is that the QEMU instance
doesn't need to have a lot of privileges to use the pre-loaded program
and the pre-created sockets, but this mentioned use-case here is different
where QEMU still needs privileges to create the sockets.
The 'map-start-index' parameter is optional and defaults to 0. It allows
flexible placement of the XSK sockets, and is up to the user to specify
when the XDP program with XSK map was already preloaded. In the simplest
case the queue-to-map-slot mapping is just 1:1 based on ctx->rx_queue_index
but the user might as well have a different scheme (or smaller map size,
e.g. ctx->rx_queue_index % max_size) to push the inbound traffic to one
of the XSK sockets.
Note that the bpf_xdp_query_id() is now only tested for 'inhibit=off'
since only in the latter case the libxdp takes care of installing the
XDP program which was installed based on the s->xdp_flags pointing to
either driver or skb mode. For 'inhibit=on' we don't make any assumptions
and neither go down the path of probing all possible options in which
way the user installed the XDP program.
Reviewed-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ilya Maximets <i.maximets@ovn.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Anton Protopopov <aspsk@isovalent.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
* rust: miscellaneous fixes
* rust: qemu-api-macros: cleanup and add unit tests for TryInto
* rust: log: implement io::Write, avoid memory allocations
when logging constant strings
* target/i386: fix usage of properties whenever accelerators
change the default (e.g. vendor)
* target/i386: add support for TDVMCALL_SETUP_EVENT_NOTIFY_INTERRUPT
* target/i386: add support for booting an SEV VM from an IGVM file
* target/i386: unify cache model descriptions between CPUID 2,
CPUID 4 and AMD specific CPUID 0x80000006
* target/i386: introduce cache models for recent Intel CPU models
* target/i386: mark some 0x80000000-0x80000008 bits as reserved on Intel
* target/i386: cleanups
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# gpg: Signature made Mon 14 Jul 2025 04:29:31 EDT
# gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg: issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1
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* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (77 commits)
i386/cpu: Honor maximum value for CPUID.8000001DH.EAX[25:14]
i386/cpu: Fix overflow of cache topology fields in CPUID.04H
i386/cpu: Fix cpu number overflow in CPUID.01H.EBX[23:16]
i386/cpu: Fix number of addressable IDs field for CPUID.01H.EBX[23:16]
i386/cpu: Reorder CPUID leaves in cpu_x86_cpuid()
tests/vm: bump FreeBSD image to 14.3
tests/functional: test_x86_cpu_model_versions: remove dead tests
i386/cpu: Mark CPUID 0x80000008 ECX bits[0:7] & [12:15] as reserved for Intel/Zhaoxin
i386/cpu: Mark CPUID 0x80000007[EBX] as reserved for Intel
i386/cpu: Mark EBX/ECX/EDX in CPUID 0x80000000 leaf as reserved for Intel
i386/cpu: Enable 0x1f leaf for YongFeng by default
i386/cpu: Enable 0x1f leaf for SapphireRapids by default
i386/cpu: Enable 0x1f leaf for GraniteRapids by default
i386/cpu: Enable 0x1f leaf for SierraForest by default
i386/cpu: Enable 0x1f leaf for SierraForest by default
i386/cpu: Add a "x-force-cpuid-0x1f" property
i386/cpu: Introduce cache model for YongFeng
i386/cpu: Introduce cache model for SapphireRapids
i386/cpu: Introduce cache model for GraniteRapids
i386/cpu: Introduce cache model for SierraForest
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The ACPI SPCR (Serial Port Console Redirection) table allows firmware
to specify a preferred serial console device to the operating system.
On ARM64 systems, Linux by default respects this table: even if the
kernel command line does not include a hardware serial console (e.g.,
"console=ttyAMA0"), the kernel still register the serial device
referenced by SPCR as a printk console.
While this behavior is standard-compliant, it can lead to situations
where guest console behavior is influenced by platform firmware rather
than user-specified configuration. To make guest console behavior more
predictable and under user control, this patch introduces a machine
option to explicitly disable SPCR table exposure:
-machine spcr=off
By default, the option is enabled (spcr=on), preserving existing
behavior. When disabled, QEMU will omit the SPCR table from the guest's
ACPI namespace, ensuring that only consoles explicitly declared in the
kernel command line are registered.
Signed-off-by: Li Chen <chenl311@chinatelecom.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Sunil V L <sunilvl@ventanamicro.com>
Message-Id: <20250528105404.457729-2-me@linux.beauty>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit adds support for the vhost-user interface to the passt
network backend, enabling high-performance, accelerated networking for
guests using passt.
The passt backend can now operate in a vhost-user mode, where it
communicates with the guest's virtio-net device over a socket pair
using the vhost-user protocol. This offloads the datapath from the
main QEMU loop, significantly improving network performance.
When the vhost-user=on option is used with -netdev passt, the new
vhost initialization path is taken instead of the standard
stream-based connection.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This commit introduces support for passt as a new network backend.
passt is an unprivileged, user-mode networking solution that provides
connectivity for virtual machines by launching an external helper process.
The implementation reuses the generic stream data handling logic. It
launches the passt binary using GSubprocess, passing it a file
descriptor from a socketpair() for communication. QEMU connects to
the other end of the socket pair to establish the network data stream.
The PID of the passt daemon is tracked via a temporary file to
ensure it is terminated when QEMU exits.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
An IGVM file contains configuration of guest state that should be
applied during configuration of the guest, before the guest is started.
This patch allows the user to add an igvm-cfg object to an X86 machine
configuration that allows an IGVM file to be configured that will be
applied to the guest before it is started.
If an IGVM configuration is provided then the IGVM file is processed at
the end of the board initialization, before the state transition to
PHASE_MACHINE_INITIALIZED.
Signed-off-by: Roy Hopkins <roy.hopkins@randomman.co.uk>
Acked-by: Gerd Hoffman <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Ani Sinha <anisinha@redhat.com>
Link: https://lore.kernel.org/r/23bc66ae4504ba5cf2134826e055b25df3fc9cd9.1751554099.git.roy.hopkins@randomman.co.uk
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The documentation for the -icount option incorrectly describes the behavior
of the sleep suboption. Based on the actual implementation and system
behavior, the effects of sleep=on and sleep=off were inadvertently reversed.
This commit updates the description to reflect their intended functionality.
Cc: qemu-stable@nongnu.org
Fixes: fa647905e6 ("qemu-options.hx: Fix minor issues in icount documentation")
Signed-off-by: Ethan Chen <ethan84@andestech.com>
Message-id: 20250606095728.3672832-1-ethan84@andestech.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Quoting Volker Rümelin: "try-poll=on tells the ALSA backend to try to
use an event loop instead of the audio timer. This works most of the
time. But the poll event handler in the ALSA backend has a bug. For
example, if the guest can't provide enough audio frames in time, the
ALSA buffer is only partly full and the event handler will be called
again and again on every iteration of the main loop. This increases
the processor load and the guest has less processor time to provide
new audio frames in time. I have two examples where a guest can't
recover from this situation and the guest seems to hang."
One reproducer I've found is booting MorphOS demo iso on
qemu-system-ppc -machine pegasos2 -audio alsa which should play a
startup sound but instead it freezes. Even when it does not hang it
plays choppy sound. Volker suggested using command line to set
try-poll=off saying: "The try-poll=off arguments are typically
necessary, because the alsa backend has a design issue with
try-poll=on. If the guest can't provide enough audio frames, it's
really unhelpful to ask for new audio frames on every main loop
iteration until the guest can provide enough audio frames. Timer based
playback doesn't have that problem."
But users cannot easily find this option and having a non-working
default is really unhelpful so to make life easier just set it to
false by default which works until the issue with the alsa backend can
be fixed.
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[ Marc-André - Updated QAPI and CLI doc ]
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20250316002046.D066A4E6004@zero.eik.bme.hu>
Locking the memory without MCL_ONFAULT instantly prefaults any mmaped
anonymous memory with a write-fault, which introduces a lot of extra
overhead in terms of memory usage when all you want to do is to prevent
kcompactd from migrating and compacting QEMU pages. Add an option to
only lock pages lazily as they're faulted by the process by using
MCL_ONFAULT if asked.
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Link: https://lore.kernel.org/r/20250212143920.1269754-5-d-tatianin@yandex-team.ru
Signed-off-by: Peter Xu <peterx@redhat.com>
1a6ed33cc5 introduced option multidevs=remap|forbid|warn and made
"warn" the default option.
As it turned out though, e.g. by several reports in conjunction with
following 9p client issue:
850925a813
Many people are just ignoring this warning, or even do not notice the
warning at all. Therefore make multidevs=remap the new default option to
prevent people to run into such kind of severe misbehaviours in the first
place.
From performance PoV the runtime overhead of multidevs=remap is
neglectable with few or even just only one device being shared with the
same 9p export, expected to be constant Theta(1). The inode numbers
emitted to guest also just loose one bit (since 6b6aa8285d) for the 1st
device being shared.
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <09cc84e5561f66b6a8cf49b3532c6c78a6acc806.1734876877.git.qemu_oss@crudebyte.com>
Add the cpr-transfer migration mode, which allows the user to transfer
a guest to a new QEMU instance on the same host with minimal guest pause
time, by preserving guest RAM in place, albeit with new virtual addresses
in new QEMU, and by preserving device file descriptors. Pages that were
locked in memory for DMA in old QEMU remain locked in new QEMU, because the
descriptor of the device that locked them remains open.
cpr-transfer preserves memory and devices descriptors by sending them to
new QEMU over a unix domain socket using SCM_RIGHTS. Such CPR state cannot
be sent over the normal migration channel, because devices and backends
are created prior to reading the channel, so this mode sends CPR state
over a second "cpr" migration channel. New QEMU reads the cpr channel
prior to creating devices or backends. The user specifies the cpr channel
in the channel arguments on the outgoing side, and in a second -incoming
command-line parameter on the incoming side.
The user must start old QEMU with the the '-machine aux-ram-share=on' option,
which allows anonymous memory to be transferred in place to the new process
by transferring a memory descriptor for each ram block. Memory-backend
objects must have the share=on attribute, but memory-backend-epc is not
supported.
The user starts new QEMU on the same host as old QEMU, with command-line
arguments to create the same machine, plus the -incoming option for the
main migration channel, like normal live migration. In addition, the user
adds a second -incoming option with channel type "cpr". This CPR channel
must support file descriptor transfer with SCM_RIGHTS, i.e. it must be a
UNIX domain socket.
To initiate CPR, the user issues a migrate command to old QEMU, adding
a second migration channel of type "cpr" in the channels argument.
Old QEMU stops the VM, saves state to the migration channels, and enters
the postmigrate state. New QEMU mmap's memory descriptors, and execution
resumes.
The implementation splits qmp_migrate into start and finish functions.
Start sends CPR state to new QEMU, which responds by closing the CPR
channel. Old QEMU detects the HUP then calls finish, which connects the
main migration channel.
In summary, the usage is:
qemu-system-$arch -machine aux-ram-share=on ...
start new QEMU with "-incoming <main-uri> -incoming <cpr-channel>"
Issue commands to old QEMU:
migrate_set_parameter mode cpr-transfer
{"execute": "migrate", ...
{"channel-type": "main"...}, {"channel-type": "cpr"...} ... }
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/r/1736967650-129648-17-git-send-email-steven.sistare@oracle.com
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Allocate auxilliary guest RAM as an anonymous file that is shareable
with an external process. This option applies to memory allocated as
a side effect of creating various devices. It does not apply to
memory-backend-objects, whether explicitly specified on the command
line, or implicitly created by the -m command line option.
This option is intended to support new migration modes, in which the
memory region can be transferred in place to a new QEMU process, by sending
the memfd file descriptor to the process. Memory contents are preserved,
and if the mode also transfers device descriptors, then pages that are
locked in memory for DMA remain locked. This behavior is a pre-requisite
for supporting vfio, vdpa, and iommufd devices with the new modes.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/1736967650-129648-7-git-send-email-steven.sistare@oracle.com
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Add new -shim command line option, wire up for the x86 loader.
When specified load shim into the new "etc/boot/shim" fw_cfg file.
Needs OVMF changes too to be actually useful.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-ID: <20240905141211.1253307-6-kraxel@redhat.com>
Do the same thing we already did for chardev in c8e2b6b4d7, and
introduce a new 'reconnect-ms' option to make it possible to specify
sub-second timeouts. This also changes the related documentaion and
tests to use reconnect-ms as well.
Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The ``-portrait`` and ``-rotate`` options were documented as only
working with the PXA LCD device, and all the machine types using
that display device were removed in 9.2.
These options were intended to simulate a mobile device being
rotated by the user, and had three effects:
* the display output was rotated by 90, 180 or 270 degrees
(implemented in the PXA display device models)
* the mouse/trackpad input was rotated the opposite way
(implemented in generic code)
* the machine model would signal to the guest about its
orientation
(implemented by e.g. the spitz machine model)
Of these three things, the input-rotation was coded without being
restricted to boards which supported the full set of device-rotation
handling, so in theory the options were usable on other machine
models with odd effects (rotating input but not display output). But
this was never intended or documented behaviour, so we can reasonably
drop these command line arguments without a formal deprecate-and-drop
cycle for them.
Remove the options, and their implementation and documentation.
Describe the removal in removed-features.rst.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003140010.1653808-7-peter.maydell@linaro.org
Add path option to the pty char backend which will create a symbolic
link to the given path that points to the allocated PTY.
This avoids having to make QMP or HMP monitor queries to find out what
the new PTY device path is.
Based on patch from Paulo Neves:
https://patchew.org/QEMU/1548509635-15776-1-git-send-email-ptsneves@gmail.com/
Tested with the following invocations that the link is created and
removed when qemu stops:
qemu-system-x86_64 -nodefaults -mon chardev=compat_monitor \
-chardev pty,path=test,id=compat_monitor0
qemu-system-x86_64 -nodefaults -monitor pty:test
# check QMP invocation with path set
qemu-system-x86_64 -nodefaults -qmp tcp:localhost:4444,server=on,wait=off
nc localhost 4444
> {"execute": "qmp_capabilities"}
> {"execute": "chardev-add", "arguments": {"id": "bar", "backend": {
"type": "pty", "data": {"path": "test" }}}}
# check QMP invocation with path not set
qemu-system-x86_64 -nodefaults -qmp tcp:localhost:4444,server=on,wait=off
nc localhost 4444
> {"execute": "qmp_capabilities"}
> {"execute": "chardev-add", "arguments": {"id": "bar", "backend": {
"type": "pty", "data": {}}}}
Also tested that when a link path is not passed invocations still work, e.g.:
qemu-system-x86_64 -monitor pty
Co-authored-by: Paulo Neves <ptsneves@gmail.com>
Signed-off-by: Paulo Neves <ptsneves@gmail.com>
[OP: rebase and address original patch review comments]
Signed-off-by: Octavian Purdila <tavip@google.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20240806010735.2450555-1-tavip@google.com>
It has been deprecated since 8.1; remove it and suggest using the 'local' file
system backend driver instead or virtiofsd.
Acked-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
"-netdev stream" supports a reconnect parameter that attempts to
reconnect automatically the socket if it is disconnected. The code
has been added but the man page has not been updated.
Fixes: 148fbf0d58 ("net: stream: add a new option to automatically reconnect"
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Add the description of "-netdev dgram" with a unix domain socket.
The code has been added but the man page has not been updated.
Fixes: 784e7a2531 ("net: dgram: add unix socket")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Add the description of "-netdev stream" with a unix domain socket.
The code has been added but the man page has not been updated.
Include an example how to use "-netdev stream" and "passt" in place
of "-netdev user".
("passt" is a non privileged translation proxy between layer-2, like
"-netdev stream", and layer-4 on host, like TCP, UDP, ICMP/ICMPv6 echo)
Fixes: 13c6be9661 ("net: stream: add unix socket")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Add the description of "-netdev stream" and "-netdev dgram" in the QEMU
manpage.
Add some examples on how to use them.
Fixes: 5166fe0ae4 ("qapi: net: add stream and dgram netdevs")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The short-form boolean options has been deprecated since v6.0 (refer
to docs/about/deprecated.rst).
Update the description and example of boolean fields in l2tpv3 option to
avoid deprecation warning.
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
