History log of /openbmc/qemu/qemu-options.hx (Results 1 – 25 of 2007)
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# 2d0530ab 22-Jan-2024 Peter Maydell <peter.maydell@linaro.org>

qemu-options.hx: Improve -serial option documentation

The -serial option documentation is a bit brief about '-serial none'
and '-serial null'. In particular it's not very clear about the
difference

qemu-options.hx: Improve -serial option documentation

The -serial option documentation is a bit brief about '-serial none'
and '-serial null'. In particular it's not very clear about the
difference between them, and it doesn't mention that it's up to
the machine model whether '-serial none' means "don't create the
serial port" or "don't wire the serial port up to anything".

Expand on these points.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240122163607.459769-3-peter.maydell@linaro.org
(cherry picked from commit 747bfaf3a9d2f3cd51674763dc1f7575100cd200)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

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# 6261164b 25-Oct-2023 Marc-André Lureau <marcandre.lureau@redhat.com>

qemu-options: define -vnc only #ifdef CONFIG_VNC

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>


# cc9d10b9 19-Oct-2023 David Woodhouse <dwmw@amazon.co.uk>

docs: update Xen-on-KVM documentation

Add notes about console and network support, and how to launch PV guests.
Clean up the disk configuration examples now that that's simpler, and
remove the comme

docs: update Xen-on-KVM documentation

Add notes about console and network support, and how to launch PV guests.
Clean up the disk configuration examples now that that's simpler, and
remove the comment about IDE unplug on q35/AHCI now that it's fixed.

Update the -initrd option documentation to explain how to quote commas
in module command lines, and reference it when documenting PV guests.

Also update stale avocado test filename in MAINTAINERS.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>

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# b2b10904 03-Oct-2023 Jean-Louis Dupond <jean-louis@dupond.be>

qcow2: keep reference on zeroize with discard-no-unref enabled

When the discard-no-unref flag is enabled, we keep the reference for
normal discard requests.
But when a discard is executed on a snaps

qcow2: keep reference on zeroize with discard-no-unref enabled

When the discard-no-unref flag is enabled, we keep the reference for
normal discard requests.
But when a discard is executed on a snapshot/qcow2 image with backing,
the discards are saved as zero clusters in the snapshot image.

When committing the snapshot to the backing file, not
discard_in_l2_slice is called but zero_in_l2_slice. Which did not had
any logic to keep the reference when discard-no-unref is enabled.

Therefor we add logic in the zero_in_l2_slice call to keep the reference
on commit.

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/1621
Signed-off-by: Jean-Louis Dupond <jean-louis@dupond.be>
Message-Id: <20231003125236.216473-2-jean-louis@dupond.be>
[hreitz: Made the documentation change more verbose, as discussed
on-list]
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>

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# 5de1aff2 16-Oct-2023 Pierre Morel <pmorel@linux.ibm.com>

CPU topology: extend with s390 specifics

S390 adds two new SMP levels, drawers and books to the CPU
topology.
S390 CPUs have specific topology features like dedication and
entitlement. These indicat

CPU topology: extend with s390 specifics

S390 adds two new SMP levels, drawers and books to the CPU
topology.
S390 CPUs have specific topology features like dedication and
entitlement. These indicate to the guest information on host
vCPU scheduling and help the guest make better scheduling decisions.

Add the new levels to the relevant QAPI structs.
Add all the supported topology levels, dedication and entitlement
as properties to S390 CPUs.
Create machine-common.json so we can later include it in
machine-target.json also.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Message-ID: <20231016183925.2384704-3-nsg@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

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# 1ebdbff4 21-Sep-2023 Paolo Bonzini <pbonzini@redhat.com>

audio: extend -audio to allow creating a default backend

If "-audio BACKEND" is used without a model, the resulting backend
will be used whenever the audiodev property is not specified.

Signed-off-

audio: extend -audio to allow creating a default backend

If "-audio BACKEND" is used without a model, the resulting backend
will be used whenever the audiodev property is not specified.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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# 385f510d 08-Sep-2023 Steve Sistare <steven.sistare@oracle.com>

migration: file URI offset

Allow an offset option to be specified as part of the file URI, in
the form "file:filename,offset=offset", where offset accepts the common
size suffixes, or the 0x prefix,

migration: file URI offset

Allow an offset option to be specified as part of the file URI, in
the form "file:filename,offset=offset", where offset accepts the common
size suffixes, or the 0x prefix, but not both. Migration data is written
to and read from the file starting at offset. If unspecified, it defaults
to 0.

This is needed by libvirt to store its own data at the head of the file.

Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <1694182931-61390-3-git-send-email-steven.sistare@oracle.com>

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# 2a9e2e59 08-Sep-2023 Steve Sistare <steven.sistare@oracle.com>

migration: file URI

Extend the migration URI to support file:<filename>. This can be used for
any migration scenario that does not require a reverse path. It can be
used as an alternative to 'exec

migration: file URI

Extend the migration URI to support file:<filename>. This can be used for
any migration scenario that does not require a reverse path. It can be
used as an alternative to 'exec:cat > file' in minimized containers that
do not contain /bin/sh, and it is easier to use than the fd:<fdname> URI.
It can be used in HMP commands, and as a qemu command-line parameter.

For best performance, guest ram should be shared and x-ignore-shared
should be true, so guest pages are not written to the file, in which case
the guest may remain running. If ram is not so configured, then the user
is advised to stop the guest first. Otherwise, a busy guest may re-dirty
the same page, causing it to be appended to the file multiple times,
and the file may grow unboundedly. That issue is being addressed in the
"fixed-ram" patch series.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Tested-by: Michael Galaxy <mgalaxy@akamai.com>
Reviewed-by: Michael Galaxy <mgalaxy@akamai.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <1694182931-61390-2-git-send-email-steven.sistare@oracle.com>

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# 69a80279 05-Sep-2023 Paolo Bonzini <pbonzini@redhat.com>

audio: remove QEMU_AUDIO_* and -audio-help support

These have been deprecated for a long time, and the introduction of
-audio in 7.1.0 has cemented the new way of specifying an audio backend's
param

audio: remove QEMU_AUDIO_* and -audio-help support

These have been deprecated for a long time, and the introduction of
-audio in 7.1.0 has cemented the new way of specifying an audio backend's
parameters. However, there is still a need for simple configuration
of the audio backend in the desktop case; therefore, if no audiodev is
passed to audio_init(), go through a bunch of simple Audiodev* structures
and pick the first that can be initialized successfully.

The only QEMU_AUDIO_* option that is left in, waiting for a better idea,
is QEMU_AUDIO_DRV=none which is used by qtest.

Remove all the parsing code, including the concept of "can_be_default"
audio drivers: now that audio_prio_list[] is only used in a single place,
wav can be excluded directly in that function.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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# e92666b0 06-Sep-2023 David Hildenbrand <david@redhat.com>

backends/hostmem-file: Add "rom" property to support VM templating with R/O files

For now, "share=off,readonly=on" would always result in us opening the
file R/O and mmap'ing the opened file MAP_PRI

backends/hostmem-file: Add "rom" property to support VM templating with R/O files

For now, "share=off,readonly=on" would always result in us opening the
file R/O and mmap'ing the opened file MAP_PRIVATE R/O -- effectively
turning it into ROM.

Especially for VM templating, "share=off" is a common use case. However,
that use case is impossible with files that lack write permissions,
because "share=off,readonly=on" will not give us writable RAM.

The sole user of ROM via memory-backend-file are R/O NVDIMMs, but as we
have users (Kata Containers) that rely on the existing behavior --
malicious VMs should not be able to consume COW memory for R/O NVDIMMs --
we cannot change the semantics of "share=off,readonly=on"

So let's add a new "rom" property with on/off/auto values. "auto" is
the default and what most people will use: for historical reasons, to not
change the old semantics, it defaults to the value of the "readonly"
property.

For VM templating, one can now use:
-object memory-backend-file,share=off,readonly=on,rom=off,...

But we'll disallow:
-object memory-backend-file,share=on,readonly=on,rom=off,...
because we would otherwise get an error when trying to mmap the R/O file
shared and writable. An explicit error message is cleaner.

We will also disallow for now:
-object memory-backend-file,share=off,readonly=off,rom=on,...
-object memory-backend-file,share=on,readonly=off,rom=on,...
It's not harmful, but also not really required for now.

Alternatives that were abandoned:
* Make "unarmed=on" for the NVDIMM set the memory region container
readonly. We would still see a change of ROM->RAM and possibly run
into memslot limits with vhost-user. Further, there might be use cases
for "unarmed=on" that should still allow writing to that memory
(temporary files, system RAM, ...).
* Add a new "readonly=on/off/auto" parameter for NVDIMMs. Similar issues
as with "unarmed=on".
* Make "readonly" consume "on/off/file" instead of being a 'bool' type.
This would slightly changes the behavior of the "readonly" parameter:
values like true/false (as accepted by a 'bool'type) would no longer be
accepted.

Message-ID: <20230906120503.359863-4-david@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

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# cb039ef3 13-Sep-2023 Ilya Maximets <i.maximets@ovn.org>

net: add initial support for AF_XDP network backend

AF_XDP is a network socket family that allows communication directly
with the network device driver in the kernel, bypassing most or all
of the ke

net: add initial support for AF_XDP network backend

AF_XDP is a network socket family that allows communication directly
with the network device driver in the kernel, bypassing most or all
of the kernel networking stack. In the essence, the technology is
pretty similar to netmap. But, unlike netmap, AF_XDP is Linux-native
and works with any network interfaces without driver modifications.
Unlike vhost-based backends (kernel, user, vdpa), AF_XDP doesn't
require access to character devices or unix sockets. Only access to
the network interface itself is necessary.

This patch implements a network backend that communicates with the
kernel by creating an AF_XDP socket. A chunk of userspace memory
is shared between QEMU and the host kernel. 4 ring buffers (Tx, Rx,
Fill and Completion) are placed in that memory along with a pool of
memory buffers for the packet data. Data transmission is done by
allocating one of the buffers, copying packet data into it and
placing the pointer into Tx ring. After transmission, device will
return the buffer via Completion ring. On Rx, device will take
a buffer form a pre-populated Fill ring, write the packet data into
it and place the buffer into Rx ring.

AF_XDP network backend takes on the communication with the host
kernel and the network interface and forwards packets to/from the
peer device in QEMU.

Usage example:

-device virtio-net-pci,netdev=guest1,mac=00:16:35:AF:AA:5C
-netdev af-xdp,ifname=ens6f1np1,id=guest1,mode=native,queues=1

XDP program bridges the socket with a network interface. It can be
attached to the interface in 2 different modes:

1. skb - this mode should work for any interface and doesn't require
driver support. With a caveat of lower performance.

2. native - this does require support from the driver and allows to
bypass skb allocation in the kernel and potentially use
zero-copy while getting packets in/out userspace.

By default, QEMU will try to use native mode and fall back to skb.
Mode can be forced via 'mode' option. To force 'copy' even in native
mode, use 'force-copy=on' option. This might be useful if there is
some issue with the driver.

Option 'queues=N' allows to specify how many device queues should
be open. Note that all the queues that are not open are still
functional and can receive traffic, but it will not be delivered to
QEMU. So, the number of device queues should generally match the
QEMU configuration, unless the device is shared with something
else and the traffic re-direction to appropriate queues is correctly
configured on a device level (e.g. with ethtool -N).
'start-queue=M' option can be used to specify from which queue id
QEMU should start configuring 'N' queues. It might also be necessary
to use this option with certain NICs, e.g. MLX5 NICs. See the docs
for examples.

In a general case QEMU will need CAP_NET_ADMIN and CAP_SYS_ADMIN
or CAP_BPF capabilities in order to load default XSK/XDP programs to
the network interface and configure BPF maps. It is possible, however,
to run with no capabilities. For that to work, an external process
with enough capabilities will need to pre-load default XSK program,
create AF_XDP sockets and pass their file descriptors to QEMU process
on startup via 'sock-fds' option. Network backend will need to be
configured with 'inhibit=on' to avoid loading of the program.
QEMU will need 32 MB of locked memory (RLIMIT_MEMLOCK) per queue
or CAP_IPC_LOCK.

There are few performance challenges with the current network backends.

First is that they do not support IO threads. This means that data
path is handled by the main thread in QEMU and may slow down other
work or may be slowed down by some other work. This also means that
taking advantage of multi-queue is generally not possible today.

Another thing is that data path is going through the device emulation
code, which is not really optimized for performance. The fastest
"frontend" device is virtio-net. But it's not optimized for heavy
traffic either, because it expects such use-cases to be handled via
some implementation of vhost (user, kernel, vdpa). In practice, we
have virtio notifications and rcu lock/unlock on a per-packet basis
and not very efficient accesses to the guest memory. Communication
channels between backend and frontend devices do not allow passing
more than one packet at a time as well.

Some of these challenges can be avoided in the future by adding better
batching into device emulation or by implementing vhost-af-xdp variant.

There are also a few kernel limitations. AF_XDP sockets do not
support any kinds of checksum or segmentation offloading. Buffers
are limited to a page size (4K), i.e. MTU is limited. Multi-buffer
support implementation for AF_XDP is in progress, but not ready yet.
Also, transmission in all non-zero-copy modes is synchronous, i.e.
done in a syscall. That doesn't allow high packet rates on virtual
interfaces.

However, keeping in mind all of these challenges, current implementation
of the AF_XDP backend shows a decent performance while running on top
of a physical NIC with zero-copy support.

Test setup:

2 VMs running on 2 physical hosts connected via ConnectX6-Dx card.
Network backend is configured to open the NIC directly in native mode.
The driver supports zero-copy. NIC is configured to use 1 queue.

Inside a VM - iperf3 for basic TCP performance testing and dpdk-testpmd
for PPS testing.

iperf3 result:
TCP stream : 19.1 Gbps

dpdk-testpmd (single queue, single CPU core, 64 B packets) results:
Tx only : 3.4 Mpps
Rx only : 2.0 Mpps
L2 FWD Loopback : 1.5 Mpps

In skb mode the same setup shows much lower performance, similar to
the setup where pair of physical NICs is replaced with veth pair:

iperf3 result:
TCP stream : 9 Gbps

dpdk-testpmd (single queue, single CPU core, 64 B packets) results:
Tx only : 1.2 Mpps
Rx only : 1.0 Mpps
L2 FWD Loopback : 0.7 Mpps

Results in skb mode or over the veth are close to results of a tap
backend with vhost=on and disabled segmentation offloading bridged
with a NIC.

Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> (docker/lcitool)
Signed-off-by: Jason Wang <jasowang@redhat.com>

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# c8f2eb5d 05-Sep-2023 Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>

arm/kvm: Enable support for KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE

Now that we have Eager Page Split support added for ARM in the kernel,
enable it in Qemu. This adds,
-eager-split-size to -accel sub-o

arm/kvm: Enable support for KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE

Now that we have Eager Page Split support added for ARM in the kernel,
enable it in Qemu. This adds,
-eager-split-size to -accel sub-options to set the eager page split chunk size.
-enable KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE.

The chunk size specifies how many pages to break at a time, using a
single allocation. Bigger the chunk size, more pages need to be
allocated ahead of time.

Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Message-id: 20230905091246.1931-1-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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# bcd8e243 29-Aug-2023 Thomas Huth <thuth@redhat.com>

qemu-options.hx: Rephrase the descriptions of the -hd* and -cdrom options

The current description says that these options will create a device
on the IDE bus, which is only true on x86. So rephrase

qemu-options.hx: Rephrase the descriptions of the -hd* and -cdrom options

The current description says that these options will create a device
on the IDE bus, which is only true on x86. So rephrase these sentences
a little bit to speak of "default bus" instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

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# b91b0fc1 23-Jun-2023 Philippe Mathieu-Daudé <philmd@linaro.org>

accel: Remove HAX accelerator

HAX is deprecated since commits 73741fda6c ("MAINTAINERS: Abort
HAXM maintenance") and 90c167a1da ("docs/about/deprecated: Mark
HAXM in QEMU as deprecated"), released i

accel: Remove HAX accelerator

HAX is deprecated since commits 73741fda6c ("MAINTAINERS: Abort
HAXM maintenance") and 90c167a1da ("docs/about/deprecated: Mark
HAXM in QEMU as deprecated"), released in v8.0.0.

Per the latest HAXM release (v7.8 [*]), the latest QEMU supported
is v7.2:

Note: Up to this release, HAXM supports QEMU from 2.9.0 to 7.2.0.

The next commit (https://github.com/intel/haxm/commit/da1b8ec072)
added:

HAXM v7.8.0 is our last release and we will not accept
pull requests or respond to issues after this.

It became very hard to build and test HAXM. Its previous
maintainers made it clear they won't help. It doesn't seem to be
a very good use of QEMU maintainers to spend their time in a dead
project. Save our time by removing this orphan zombie code.

[*] https://github.com/intel/haxm/releases/tag/v7.8.0

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230831082016.60885-1-philmd@linaro.org>

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# 01bf87c8 29-Aug-2023 Thomas Huth <thuth@redhat.com>

qemu-options.hx: Rephrase the descriptions of the -hd* and -cdrom options

The current description says that these options will create a device
on the IDE bus, which is only true on x86. So rephrase

qemu-options.hx: Rephrase the descriptions of the -hd* and -cdrom options

The current description says that these options will create a device
on the IDE bus, which is only true on x86. So rephrase these sentences
a little bit to speak of "default bus" instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
(cherry picked from commit bcd8e243083c878884e52d609deddbe6be17c730)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

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# 20c51248 06-May-2023 Marc-André Lureau <marcandre.lureau@redhat.com>

audio/pw: Pipewire->PipeWire case fix for user-visible text

"PipeWire" is the correct case.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philm

audio/pw: Pipewire->PipeWire case fix for user-visible text

"PipeWire" is the correct case.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20230506163735.3481387-4-marcandre.lureau@redhat.com>

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# 9ffcbe2a 03-Jul-2023 Thomas Huth <thuth@redhat.com>

os-posix: Allow 'chroot' via '-run-with' and deprecate the old '-chroot' option

We recently introduced "-run-with" for options that influence the
runtime behavior of QEMU. This option has the big ad

os-posix: Allow 'chroot' via '-run-with' and deprecate the old '-chroot' option

We recently introduced "-run-with" for options that influence the
runtime behavior of QEMU. This option has the big advantage that it
can group related options (so that it is easier for the users to spot
them) and that the options become introspectable via QMP this way.
So let's start moving more switches into this option group, starting
with "-chroot" now.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Message-Id: <20230703074447.17044-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

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# a635bcfc 03-Jul-2023 Thomas Huth <thuth@redhat.com>

qemu-options.hx: Fix indentation of some option descriptions

The description of the options starts at column 16, so fix
this in some runaway lines for a more uniform output.

While we're at it, repl

qemu-options.hx: Fix indentation of some option descriptions

The description of the options starts at column 16, so fix
this in some runaway lines for a more uniform output.

While we're at it, replace the capital "NOTE" with "Note"
since this seems to be the more common capitalization in
qemu-options.hx.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

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# c35d9373 28-Jun-2023 Jan Kratochvil <jan@jankratochvil.net>

trivial: man page: document display::gtk::zoom-to-fit

Document display::gtk::zoom-to-fit.

info from: https://superuser.com/questions/1752209/qemu-zoom-to-fit-shortcut-or-cli-switch

Signed-off-by:

trivial: man page: document display::gtk::zoom-to-fit

Document display::gtk::zoom-to-fit.

info from: https://superuser.com/questions/1752209/qemu-zoom-to-fit-shortcut-or-cli-switch

Signed-off-by: Jan Kratochvil <jan@jankratochvil.net>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

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# 71d72ece 26-Jun-2023 Christian Schoenebeck <qemu_oss@crudebyte.com>

9pfs: deprecate 'proxy' backend

As recent CVE-2023-2861 (fixed by f6b0de53fb) once again showed, the 9p
'proxy' fs driver is in bad shape. Using the 'proxy' backend was already
discouraged for safet

9pfs: deprecate 'proxy' backend

As recent CVE-2023-2861 (fixed by f6b0de53fb) once again showed, the 9p
'proxy' fs driver is in bad shape. Using the 'proxy' backend was already
discouraged for safety reasons before and we recommended to use the
'local' backend (preferably in conjunction with its 'mapped' security
model) instead, but now it is time to officially deprecate the 'proxy'
backend.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1qDkmw-0007M1-8f@lizzy.crudebyte.com>

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# 42a2890a 05-Jun-2023 Jean-Louis Dupond <jean-louis@dupond.be>

qcow2: add discard-no-unref option

When we for example have a sparse qcow2 image and discard: unmap is enabled,
there can be a lot of fragmentation in the image after some time. Especially on VM's
t

qcow2: add discard-no-unref option

When we for example have a sparse qcow2 image and discard: unmap is enabled,
there can be a lot of fragmentation in the image after some time. Especially on VM's
that do a lot of writes/deletes.
This causes the qcow2 image to grow even over 110% of its virtual size,
because the free gaps in the image get too small to allocate new
continuous clusters. So it allocates new space at the end of the image.

Disabling discard is not an option, as discard is needed to keep the
incremental backup size as low as possible. Without discard, the
incremental backups would become large, as qemu thinks it's just dirty
blocks but it doesn't know the blocks are unneeded.
So we need to avoid fragmentation but also 'empty' the unneeded blocks in
the image to have a small incremental backup.

In addition, we also want to send the discards further down the stack, so
the underlying blocks are still discarded.

Therefor we introduce a new qcow2 option "discard-no-unref".
When setting this option to true, discards will no longer have the qcow2
driver relinquish cluster allocations. Other than that, the request is
handled as normal: All clusters in range are marked as zero, and, if
pass-discard-request is true, it is passed further down the stack.
The only difference is that the now-zero clusters are preallocated
instead of being unallocated.
This will avoid fragmentation on the qcow2 image.

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/1621
Signed-off-by: Jean-Louis Dupond <jean-louis@dupond.be>
Message-Id: <20230605084523.34134-2-jean-louis@dupond.be>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>

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Revision tags: v8.0.0
# 4b870dc4 03-Apr-2023 Alexander Graf <graf@amazon.com>

hostmem-file: add offset option

Add an option for hostmem-file to start the memory object at an offset
into the target file. This is useful if multiple memory objects reside
inside the same target f

hostmem-file: add offset option

Add an option for hostmem-file to start the memory object at an offset
into the target file. This is useful if multiple memory objects reside
inside the same target file, such as a device node.

In particular, it's useful to map guest memory directly into /dev/mem
for experimentation.

To make this work consistently, also fix up all places in QEMU that
expect fd offsets to be 0.

Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20230403221421.60877-1-graf@amazon.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

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# 0ec4468f 15-May-2023 Peter Maydell <peter.maydell@linaro.org>

docs/interop: Delete qmp-intro.txt

qmp-intro.txt is quite small and provides very little information
that isn't already in the documentation elsewhere. Fold the example
command lines into qemu-opti

docs/interop: Delete qmp-intro.txt

qmp-intro.txt is quite small and provides very little information
that isn't already in the documentation elsewhere. Fold the example
command lines into qemu-options.hx, and delete the now-unneeded plain
text document.

While we're touching the qemu-options.hx documentation text,
wordsmith it a little bit and improve the rST formatting.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230515162245.3964307-4-peter.maydell@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

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# 80bd81ca 05-May-2023 Claudio Imbrenda <imbrenda@linux.ibm.com>

util/async-teardown: wire up query-command-line-options

Add new -run-with option with an async-teardown=on|off parameter. It is
visible in the output of query-command-line-options QMP command, so it

util/async-teardown: wire up query-command-line-options

Add new -run-with option with an async-teardown=on|off parameter. It is
visible in the output of query-command-line-options QMP command, so it
can be discovered and used by libvirt.

The option -async-teardown is now redundant, deprecate it.

Reported-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Fixes: c891c24b1a ("os-posix: asynchronous teardown for shutdown on Linux")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20230505120051.36605-2-imbrenda@linux.ibm.com>
[thuth: Add curly braces to fix error with GCC 8.5, fix bug in deprecated.rst]
Signed-off-by: Thomas Huth <thuth@redhat.com>

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# c2d3d1c2 17-Apr-2023 Dorinda Bassey <dbassey@redhat.com>

audio/pwaudio.c: Add Pipewire audio backend for QEMU

This commit adds a new audiodev backend to allow QEMU to use Pipewire as
both an audio sink and source. This backend is available on most systems

audio/pwaudio.c: Add Pipewire audio backend for QEMU

This commit adds a new audiodev backend to allow QEMU to use Pipewire as
both an audio sink and source. This backend is available on most systems

Add Pipewire entry points for QEMU Pipewire audio backend
Add wrappers for QEMU Pipewire audio backend in qpw_pcm_ops()
qpw_write function returns the current state of the stream to pwaudio
and Writes some data to the server for playback streams using pipewire
spa_ringbuffer implementation.
qpw_read function returns the current state of the stream to pwaudio and
reads some data from the server for capture streams using pipewire
spa_ringbuffer implementation. These functions qpw_write and qpw_read
are called during playback and capture.
Added some functions that convert pw audio formats to QEMU audio format
and vice versa which would be needed in the pipewire audio sink and
source functions qpw_init_in() & qpw_init_out().
These methods that implement playback and recording will create streams
for playback and capture that will start processing and will result in
the on_process callbacks to be called.
Built a connection to the Pipewire sound system server in the
qpw_audio_init() method.

Signed-off-by: Dorinda Bassey <dbassey@redhat.com>
Reviewed-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20230417105654.32328-1-dbassey@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>

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