Commit Graph

833 Commits

Author SHA1 Message Date
Yihuan Pan
fd49b2153e qemu-options: Clarify handling of commas in options parameters
Provide explicit guidance on dealing with option parameters as arbitrary
strings containing commas, such as in "file=my,file" and "string=a,b". The
updated documentation emphasizes the need to double commas when they
appear within such parameters.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1839
Signed-off-by: Yihuan Pan <xun794@gmail.com>
Message-ID: <20231213141706.629833-2-xun794@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2023-12-20 10:29:23 +01:00
Stefan Hajnoczi
462ad017ed Make Pixman an optional dependency
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Merge tag 'pixman-pull-request' of https://gitlab.com/marcandre.lureau/qemu into staging

Make Pixman an optional dependency

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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 'pixman-pull-request' of https://gitlab.com/marcandre.lureau/qemu: (25 commits)
  build-sys: make pixman actually optional
  hw/display/ati: allow compiling without PIXMAN
  hw/mips: FULOONG depends on VT82C686
  hw/sm501: allow compiling without PIXMAN
  hw/arm: XLNX_VERSAL depends on XLNX_CSU_DMA
  arm/kconfig: XLNX_ZYNQMP_ARM depends on PIXMAN
  ui/dbus: do not require PIXMAN
  ui/gtk: -display gtk requires PIXMAN
  ui/spice: SPICE/QXL requires PIXMAN
  ui/vnc: VNC requires PIXMAN
  ui/gl: opengl doesn't require PIXMAN
  vhost-user-gpu: skip VHOST_USER_GPU_UPDATE when !PIXMAN
  ui/console: when PIXMAN is unavailable, don't draw placeholder msg
  virtio-gpu: replace PIXMAN for region/rect test
  qmp/hmp: disable screendump if PIXMAN is missing
  ui/vc: console-vc requires PIXMAN
  ui/console: allow to override the default VC
  vl: move display early init before default devices
  vl: simplify display_remote logic
  qemu-options: define -vnc only #ifdef CONFIG_VNC
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-11-07 19:00:03 +08:00
Marc-André Lureau
6261164bd6 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>
2023-11-07 14:04:25 +04:00
David Woodhouse
cc9d10b9e8 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>
2023-11-07 08:58:02 +00:00
Jean-Louis Dupond
b2b109041e 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>
2023-11-06 16:15:07 +01:00
Pierre Morel
5de1aff255 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>
2023-10-20 07:16:53 +02:00
Paolo Bonzini
1ebdbff4c3 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>
2023-10-08 21:08:27 +02:00
Steve Sistare
385f510df5 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>
2023-10-04 13:18:08 +02:00
Steve Sistare
2a9e2e595f 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>
2023-10-04 13:16:58 +02:00
Paolo Bonzini
69a802792a 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>
2023-10-03 10:29:39 +02:00
Stefan Hajnoczi
4907644841 Hi,
"Host Memory Backends" and "Memory devices" queue ("mem"):
 - Support and document VM templating with R/O files using a new "rom"
   parameter for memory-backend-file
 - Some cleanups and fixes around NVDIMMs and R/O file handling for guest
   RAM
 - Optimize ioeventfd updates by skipping address spaces that are not
   applicable
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Merge tag 'mem-2023-09-19' of https://github.com/davidhildenbrand/qemu into staging

Hi,

"Host Memory Backends" and "Memory devices" queue ("mem"):
- Support and document VM templating with R/O files using a new "rom"
  parameter for memory-backend-file
- Some cleanups and fixes around NVDIMMs and R/O file handling for guest
  RAM
- Optimize ioeventfd updates by skipping address spaces that are not
  applicable

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# gpg:                using RSA key 1BD9CAAD735C4C3A460DFCCA4DDE10F700FF835A
# gpg:                issuer "david@redhat.com"
# gpg: Good signature from "David Hildenbrand <david@redhat.com>" [unknown]
# gpg:                 aka "David Hildenbrand <davidhildenbrand@gmail.com>" [full]
# gpg:                 aka "David Hildenbrand <hildenbr@in.tum.de>" [unknown]
# gpg: WARNING: The key's User ID is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 1BD9 CAAD 735C 4C3A 460D  FCCA 4DDE 10F7 00FF 835A

* tag 'mem-2023-09-19' of https://github.com/davidhildenbrand/qemu:
  memory: avoid updating ioeventfds for some address_space
  machine: Improve error message when using default RAM backend id
  softmmu/physmem: Hint that "readonly=on,rom=off" exists when opening file R/W for private mapping fails
  docs: Start documenting VM templating
  docs: Don't mention "-mem-path" in multi-process.rst
  softmmu/physmem: Never return directories from file_ram_open()
  softmmu/physmem: Fail creation of new files in file_ram_open() with readonly=true
  softmmu/physmem: Bail out early in ram_block_discard_range() with readonly files
  softmmu/physmem: Remap with proper protection in qemu_ram_remap()
  backends/hostmem-file: Add "rom" property to support VM templating with R/O files
  softmmu/physmem: Distinguish between file access mode and mmap protection
  nvdimm: Reject writing label data to ROM instead of crashing QEMU

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-09-19 13:22:19 -04:00
David Hildenbrand
e92666b0ba 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>
2023-09-19 10:23:21 +02:00
Ilya Maximets
cb039ef3d9 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>
2023-09-18 14:36:13 +08:00
Stefan Hajnoczi
a7e8e30e7c target-arm queue:
* New CPU type: cortex-a710
  * Implement new architectural features:
     - FEAT_PACQARMA3
     - FEAT_EPAC
     - FEAT_Pauth2
     - FEAT_FPAC
     - FEAT_FPACCOMBINE
     - FEAT_TIDCP1
  * Xilinx Versal: Model the CFU/CFI
  * Implement RMR_ELx registers
  * Implement handling of HCR_EL2.TIDCP trap bit
  * arm/kvm: Enable support for KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE
  * hw/intc/arm_gicv3_its: Avoid maybe-uninitialized error in get_vte()
  * target/arm: Do not use gen_mte_checkN in trans_STGP
  * arm64: Restore trapless ptimer access
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Merge tag 'pull-target-arm-20230908' of https://git.linaro.org/people/pmaydell/qemu-arm into staging

target-arm queue:
 * New CPU type: cortex-a710
 * Implement new architectural features:
    - FEAT_PACQARMA3
    - FEAT_EPAC
    - FEAT_Pauth2
    - FEAT_FPAC
    - FEAT_FPACCOMBINE
    - FEAT_TIDCP1
 * Xilinx Versal: Model the CFU/CFI
 * Implement RMR_ELx registers
 * Implement handling of HCR_EL2.TIDCP trap bit
 * arm/kvm: Enable support for KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE
 * hw/intc/arm_gicv3_its: Avoid maybe-uninitialized error in get_vte()
 * target/arm: Do not use gen_mte_checkN in trans_STGP
 * arm64: Restore trapless ptimer access

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# gpg: Signature made Fri 08 Sep 2023 13:05:13 EDT
# gpg:                using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg:                issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [full]
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [full]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [full]
# gpg:                 aka "Peter Maydell <peter@archaic.org.uk>" [unknown]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* tag 'pull-target-arm-20230908' of https://git.linaro.org/people/pmaydell/qemu-arm: (26 commits)
  arm/kvm: Enable support for KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE
  target/arm: Enable SCTLR_EL1.TIDCP for user-only
  target/arm: Implement FEAT_TIDCP1
  target/arm: Implement HCR_EL2.TIDCP
  target/arm: Implement cortex-a710
  target/arm: Implement RMR_ELx
  arm64: Restore trapless ptimer access
  target/arm: Do not use gen_mte_checkN in trans_STGP
  hw/arm/versal: Connect the CFRAME_REG and CFRAME_BCAST_REG
  hw/arm/xlnx-versal: Connect the CFU_APB, CFU_FDRO and CFU_SFR
  hw/misc: Introduce a model of Xilinx Versal's CFRAME_BCAST_REG
  hw/misc: Introduce a model of Xilinx Versal's CFRAME_REG
  hw/misc/xlnx-versal-cfu: Introduce a model of Xilinx Versal's CFU_SFR
  hw/misc/xlnx-versal-cfu: Introduce a model of Xilinx Versal CFU_FDRO
  hw/misc: Introduce a model of Xilinx Versal's CFU_APB
  hw/misc: Introduce the Xilinx CFI interface
  hw/intc/arm_gicv3_its: Avoid maybe-uninitialized error in get_vte()
  target/arm: Implement FEAT_FPAC and FEAT_FPACCOMBINE
  target/arm: Inform helpers whether a PAC instruction is 'combined'
  target/arm: Implement FEAT_Pauth2
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-09-11 09:10:37 -04:00
Shameer Kolothum
c8f2eb5d41 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>
2023-09-08 16:41:36 +01:00
Thomas Huth
bcd8e24308 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>
2023-09-08 13:08:52 +03:00
Philippe Mathieu-Daudé
b91b0fc163 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>
2023-08-31 19:46:43 +02:00
Marc-André Lureau
20c5124805 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>
2023-07-17 15:22:56 +04:00
Thomas Huth
9ffcbe2a60 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>
2023-07-10 15:34:57 +02:00
Thomas Huth
a635bcfc7a 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>
2023-07-08 07:24:38 +03:00
Jan Kratochvil
c35d9373be 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>
2023-07-08 07:24:38 +03:00
Christian Schoenebeck
71d72ececa 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>
2023-07-06 11:42:08 +02:00
Jean-Louis Dupond
42a2890a76 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>
2023-06-05 13:15:42 +02:00
Alexander Graf
4b870dc4d0 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>
2023-05-23 16:47:03 +02:00
Peter Maydell
0ec4468f23 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>
2023-05-22 10:22:29 +02:00
Claudio Imbrenda
80bd81cadd 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>
2023-05-16 09:14:18 +02:00
Dorinda Bassey
c2d3d1c294 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>
2023-05-05 13:23:08 +04:00
Peter Maydell
12fd0f41d0 Document that -singlestep command line option is deprecated
Document that the -singlestep command line option is now
deprecated, as it is replaced by either the TCG accelerator
property 'one-insn-per-tb' for system emulation or the new
'-one-insn-per-tb' option for usermode emulation, and remove
the only use of the deprecated syntax from a README.

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: 20230417164041.684562-7-peter.maydell@linaro.org
2023-05-02 15:47:40 +01:00
Peter Maydell
3cfb0456c3 make one-insn-per-tb an accel option
This commit adds 'one-insn-per-tb' as a property on the TCG
accelerator object, so you can enable it with
   -accel tcg,one-insn-per-tb=on

It has the same behaviour as the existing '-singlestep' command line
option.  We use a different name because 'singlestep' has always been
a confusing choice, because it doesn't have anything to do with
single-stepping the CPU.  What it does do is force TCG emulation to
put one guest instruction in each TB, which can be useful in some
situations (such as analysing debug logs).

The existing '-singlestep' commandline options are decoupled from the
global 'singlestep' variable and instead now are syntactic sugar for
setting the accel property.  (These can then go away after a
deprecation period.)

The global variable remains for the moment as:
 * what the TCG code looks at to change its behaviour
 * what HMP and QMP use to query and set the behaviour

In the following commits we'll clean those up to not directly
look at the global variable.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230417164041.684562-2-peter.maydell@linaro.org
2023-05-02 15:47:40 +01:00
Tom Lendacky
326e3015c4 qemu-options.hx: Update the reduced-phys-bits documentation
A guest only ever experiences, at most, 1 bit of reduced physical
addressing. Update the documentation to reflect this as well as change
the example value on the reduced-phys-bits option.

Fixes: a9b4942f48 ("target/i386: add Secure Encrypted Virtualization (SEV) object")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <13a62ced1808546c1d398e2025cf85f4c94ae123.1664550870.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-04-28 12:50:34 +02:00
Yohei Kojima
4f513984ed qemu-options.hx: Update descriptions of memory options for NUMA node
This commit adds the following description:
1. `memdev` option is recommended over `mem` option (see [1,2])
2. users must specify memory for all NUMA nodes (see [2])

This commit also separates descriptions for `mem` and `memdev` into two
paragraphs. The old doc describes legacy `mem` option first, and it was
a bit confusing.

Related documentation:
[1] https://wiki.qemu.org/ChangeLog/5.1#Incompatible_changes
[2] https://www.qemu.org/docs/master/about/removed-features.html

Signed-off-by: Yohei Kojima <y-koj@outlook.jp>
Message-Id: <TYZPR06MB5418D6B0175A49E8E76988439D8E9@TYZPR06MB5418.apcprd06.prod.outlook.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[AJB: fix documentation in commit message]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230424092249.58552-15-alex.bennee@linaro.org>
2023-04-27 14:58:29 +01:00
Alex Bennée
c1654c3e37 qemu-options: finesse the recommendations around -blockdev
We are a bit premature in recommending -blockdev/-device as the best
way to configure block devices. It seems there are times the more
human friendly -drive still makes sense especially when -snapshot is
involved.

Improve the language to hopefully make things clearer.

Suggested-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230424092249.58552-7-alex.bennee@linaro.org>
2023-04-27 14:58:17 +01:00
Peter Maydell
5b18a6bf44 chardev: Allow setting file chardev input file on the command line
Our 'file' chardev backend supports both "output from this chardev
is written to a file" and "input from this chardev should be read
from a file" (except on Windows). However, you can only set up
the input file if you're using the QMP interface -- there is no
command line syntax to do it.

Add command line syntax to allow specifying an input file
as well as an output file, using a new 'input-path' suboption.

The specific use case I have is that I'd like to be able to
feed fuzzer reproducer input into qtest without having to use
'-qtest stdio' and put the input onto stdin. Being able to
use a file chardev like this:
 -chardev file,id=repro,path=/dev/null,input-path=repro.txt -qtest chardev:repro
means that stdio is free for use by gdb.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230413150724.404304-3-peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[thuth: Replace "input-file=" typo with "input-path="]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2023-04-20 06:50:11 +02:00
John Snow
a234ec311b qemu-options.hx: remove stray quote
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230202223121.252073-1-jsnow@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2023-03-13 18:36:38 +01:00
Song Gao
4934cc5850
loongarch: Add smbios command line option.
LoongArch has enabled CONFIG_SMBIOS, but didn't enable CLI '-smbios'.

Fixes: 3efa6fa1e6 ("hw/loongarch: Add smbios support")
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20230227035905.1290953-2-gaosong@loongson.cn>
2023-03-03 09:37:29 +08:00
Laurent Vivier
148fbf0d58 net: stream: add a new option to automatically reconnect
In stream mode, if the server shuts down there is currently
no way to reconnect the client to a new server without removing
the NIC device and the netdev backend (or to reboot).

This patch introduces a reconnect option that specifies a delay
to try to reconnect with the same parameters.

Add a new test in qtest to test the reconnect option and the
connect/disconnect events.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2023-02-17 13:31:33 +08:00
Daniel P. Berrangé
36debafddd ui: remove deprecated 'password' option for SPICE
This has been replaced by the 'password-secret' option,
which references a 'secret' object instance.

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2023-02-15 11:14:58 -05:00
Daniel P. Berrangé
c3b3a6c956 block: mention 'password-secret' option for -iscsi
The 'password-secret' option was added

  commit b189346eb1
  Author: Daniel P. Berrangé <berrange@redhat.com>
  Date:   Thu Jan 21 14:19:21 2016 +0000

    iscsi: add support for getting CHAP password via QCryptoSecret API

but was not mentioned in the command line docs

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2023-02-15 11:01:04 -05:00
Alex Bennée
2da9d21360 semihosting: add semihosting section to the docs
The main reason to do this is to document our O_BINARY implementation
decision somewhere. However I've also moved some of the implementation
details out of qemu-options and added links between the two. As a
bonus I've highlighted the scary warnings about host access with the
appropriate RST tags.

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-22-alex.bennee@linaro.org>
2023-02-02 10:44:23 +00:00
Ilya Leoshkevich
5584e2dbe8 tcg: add perfmap and jitdump
Add ability to dump /tmp/perf-<pid>.map and jit-<pid>.dump.
The first one allows the perf tool to map samples to each individual
translation block. The second one adds the ability to resolve symbol
names, line numbers and inspect JITed code.

Example of use:

    perf record qemu-x86_64 -perfmap ./a.out
    perf report

or

    perf record -k 1 qemu-x86_64 -jitdump ./a.out
    DEBUGINFOD_URLS= perf inject -j -i perf.data -o perf.data.jitted
    perf report -i perf.data.jitted

Co-developed-by: Vanderson M. do Rosario <vandersonmr2@gmail.com>
Co-developed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230112152013.125680-4-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-01-16 10:14:12 -10:00
Peter Maydell
aa96ab7c9d * s390x header clean-ups from Philippe
* Rework and improvements of the EINTR handling by Nikita
 * Deprecate the -no-hpet command line option
 * Disable the qtests in the 32-bit Windows CI job again
 * Some other misc fixes here and there
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Merge tag 'pull-request-2023-01-09' of https://gitlab.com/thuth/qemu into staging

* s390x header clean-ups from Philippe
* Rework and improvements of the EINTR handling by Nikita
* Deprecate the -no-hpet command line option
* Disable the qtests in the 32-bit Windows CI job again
* Some other misc fixes here and there

# gpg: Signature made Mon 09 Jan 2023 14:21:19 GMT
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* tag 'pull-request-2023-01-09' of https://gitlab.com/thuth/qemu:
  .gitlab-ci.d/windows: Do not run the qtests in the msys2-32bit job
  error handling: Use RETRY_ON_EINTR() macro where applicable
  Refactoring: refactor TFR() macro to RETRY_ON_EINTR()
  docs/interop: Change the vnc-ledstate-Pseudo-encoding doc into .rst
  i386: Deprecate the -no-hpet QEMU command line option
  tests/qtest/bios-tables-test: Replace -no-hpet with hpet=off machine parameter
  tests/readconfig: spice doesn't support unix socket on windows yet
  target/s390x: Restrict sysemu/reset.h to system emulation
  target/s390x/tcg/excp_helper: Restrict system headers to sysemu
  target/s390x/tcg/misc_helper: Remove unused "memory.h" include
  hw/s390x/pv: Restrict Protected Virtualization to sysemu
  exec/memory: Expose memory_region_access_valid()
  MAINTAINERS: Add MIPS-related docs and configs to the MIPS architecture section
  tests/vm: Update get_default_jobs() to work on non-x86_64 non-KVM hosts
  qemu-iotests/stream-under-throttle: do not shutdown QEMU

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-01-09 15:54:31 +00:00
Thomas Huth
df37330c05 i386: Deprecate the -no-hpet QEMU command line option
The HPET setting has been turned into a machine property a while ago
already, so we should finally do the next step and deprecate the
legacy CLI option, too.

Message-Id: <20221229114913.260400-1-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2023-01-09 13:50:47 +01:00
Peter Maydell
d6271b6572 virtio,pc,pci: features, cleanups, fixes
mostly vhost-vdpa:
     guest announce feature emulation when using shadow virtqueue
     support for configure interrupt
     startup speed ups
 
 an acpi change to only generate cluster node in PPTT when specified for arm
 
 misc fixes, cleanups
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

virtio,pc,pci: features, cleanups, fixes

mostly vhost-vdpa:
    guest announce feature emulation when using shadow virtqueue
    support for configure interrupt
    startup speed ups

an acpi change to only generate cluster node in PPTT when specified for arm

misc fixes, cleanups

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Sun 08 Jan 2023 08:01:39 GMT
# gpg:                using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg:                issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (50 commits)
  vhost-scsi: fix memleak of vsc->inflight
  acpi: cpuhp: fix guest-visible maximum access size to the legacy reg block
  tests: acpi: aarch64: Add *.topology tables
  tests: acpi: aarch64: Add topology test for aarch64
  tests: acpi: Add and whitelist *.topology blobs
  tests: virt: Update expected ACPI tables for virt test
  hw/acpi/aml-build: Only generate cluster node in PPTT when specified
  tests: virt: Allow changes to PPTT test table
  virtio-pci: fix proxy->vector_irqfd leak in virtio_pci_set_guest_notifiers
  vdpa: commit all host notifier MRs in a single MR transaction
  vhost: configure all host notifiers in a single MR transaction
  vhost: simplify vhost_dev_enable_notifiers
  vdpa: harden the error path if get_iova_range failed
  vdpa-dev: get iova range explicitly
  docs/devel: Rules on #include in headers
  include: Include headers where needed
  include/hw/virtio: Break inclusion loop
  include/hw/cxl: Break inclusion loop cxl_pci.h and cxl_cdat_h
  include/hw/pci: Include hw/pci/pci.h where needed
  include/hw/pci: Split pci_device.h off pci.h
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-01-09 10:07:12 +00:00
Yicong Yang
97f4effeb6 hw/acpi/aml-build: Only generate cluster node in PPTT when specified
Currently we'll always generate a cluster node no matter user has
specified '-smp clusters=X' or not. Cluster is an optional level
and will participant the building of Linux scheduling domains and
only appears on a few platforms. It's unncessary to always build
it when it cannot reflect the real topology on platforms having no
cluster implementation and to avoid affecting the linux scheduling
domains in the VM. So only generate the cluster topology in ACPI
PPTT when the user has specified it explicitly in -smp.

Tested qemu-system-aarch64 with `-smp 8` and linux 6.1-rc1, without
this patch:
estuary:/sys/devices/system/cpu/cpu0/topology$ cat cluster_*
ff	# cluster_cpus
0-7	# cluster_cpus_list
56	# cluster_id

with this patch:
estuary:/sys/devices/system/cpu/cpu0/topology$ cat cluster_*
ff	# cluster_cpus
0-7	# cluster_cpus_list
36	# cluster_id, with no cluster node kernel will make it to
	  physical package id

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Yanan Wang <wangyanan55@huawei.com>
Tested-by: Yanan Wang <wangyanan55@huawei.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Message-Id: <20221229065513.55652-3-yangyicong@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-08 01:54:23 -05:00
Paolo Bonzini
6f9f630836 util: remove support -chardev tty and -chardev parport
These were deprecated in 6.0 and can now be removed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-01-06 00:51:02 +01:00
Stefan Weil
2cb40d446f Fix several typos in documentation (found by codespell)
Those typos are in files which are used to generate the QEMU manual.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Message-Id: <20221110190825.879620-1-sw@weilnetz.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Ani Sinha <ani@anisinha.ca>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
[thuth: update sentence in can.rst as suggested by Peter]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-11-11 09:39:25 +01:00
Cédric Le Goater
5770289137 Revert "s390x/s390-virtio-ccw: add zpcii-disable machine property"
This reverts commit 59d1ce4439.

The "zpcii-disable" machine property is redundant with the "interpret"
zPCI device property. Remove it for clarification.

Signed-off-by: Cédric Le Goater <clg@redhat.com>
Message-Id: <20221107161349.1032730-2-clg@kaod.org>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-11-08 10:10:57 +01:00
Stefan Weil
1e458f1127 Fix some typos in documentation and comments
Most of them were found and fixed using codespell.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20221030105944.311940-1-sw@weilnetz.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-11-05 20:35:45 +01:00
Stefan Hajnoczi
7f5acfcb66 * bug fixes
* reduced memory footprint for IPI virtualization on Intel processors
 * asynchronous teardown support (Linux only)
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Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging

* bug fixes
* reduced memory footprint for IPI virtualization on Intel processors
* asynchronous teardown support (Linux only)

# -----BEGIN PGP SIGNATURE-----
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# gpg: Signature made Wed 02 Nov 2022 07:40:25 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
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* tag 'for-upstream' of https://gitlab.com/bonzini/qemu:
  target/i386: Fix test for paging enabled
  util/log: Close per-thread log file on thread termination
  target/i386: Set maximum APIC ID to KVM prior to vCPU creation
  os-posix: asynchronous teardown for shutdown on Linux
  target/i386: Fix calculation of LOCK NEG eflags

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-11-03 10:54:37 -04:00
Claudio Imbrenda
c891c24b1a os-posix: asynchronous teardown for shutdown on Linux
This patch adds support for asynchronously tearing down a VM on Linux.

When qemu terminates, either naturally or because of a fatal signal,
the VM is torn down. If the VM is huge, it can take a considerable
amount of time for it to be cleaned up. In case of a protected VM, it
might take even longer than a non-protected VM (this is the case on
s390x, for example).

Some users might want to shut down a VM and restart it immediately,
without having to wait. This is especially true if management
infrastructure like libvirt is used.

This patch implements a simple trick on Linux to allow qemu to return
immediately, with the teardown of the VM being performed
asynchronously.

If the new commandline option -async-teardown is used, a new process is
spawned from qemu at startup, using the clone syscall, in such way that
it will share its address space with qemu.The new process will have the
name "cleanup/<QEMU_PID>". It will wait until qemu terminates
completely, and then it will exit itself.

This allows qemu to terminate quickly, without having to wait for the
whole address space to be torn down. The cleanup process will exit
after qemu, so it will be the last user of the address space, and
therefore it will take care of the actual teardown. The cleanup
process will share the same cgroups as qemu, so both memory usage and
cpu time will be accounted properly.

If possible, close_range will be used in the cleanup process to close
all open file descriptors. If it is not available or if it fails, /proc
will be used to determine which file descriptors to close.

If the cleanup process is forcefully killed with SIGKILL before the
main qemu process has terminated completely, the mechanism is defeated
and the teardown will not be asynchronous.

This feature can already be used with libvirt by adding the following
to the XML domain definition to pass the parameter to qemu directly:

  <commandline xmlns="http://libvirt.org/schemas/domain/qemu/1.0">
  <arg value='-async-teardown'/>
  </commandline>

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Tested-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Message-Id: <20220812133453.82671-1-imbrenda@linux.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-10-31 09:46:34 +01:00