Commit Graph

769 Commits

Author SHA1 Message Date
Alexandre Ratchov
663df1cc68 audio: Add sndio backend
sndio is the native API used by OpenBSD, although it has been ported to
other *BSD's and Linux (packages for Ubuntu, Debian, Void, Arch, etc.).

Signed-off-by: Brad Smith <brad@comstyle.com>
Signed-off-by: Alexandre Ratchov <alex@caoua.org>
Reviewed-by: Volker Rümelin <vr_qemu@t-online.de>
Tested-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <YxibXrWsrS3XYQM3@vm1.arverb.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2022-09-27 07:32:31 +02:00
Claudio Fontana
5e03b6daf6 audio: add help option for -audio and -audiodev
add a simple help option for -audio and -audiodev
to show the list of available drivers, and document them.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20220908081441.7111-1-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-19 15:15:59 +02:00
Peter Maydell
5202861b20 semihosting: Allow optional use of semihosting from userspace
Currently our semihosting implementations generally prohibit use of
semihosting calls in system emulation from the guest userspace.  This
is a very long standing behaviour justified originally "to provide
some semblance of security" (since code with access to the
semihosting ABI can do things like read and write arbitrary files on
the host system).  However, it is sometimes useful to be able to run
trusted guest code which performs semihosting calls from guest
userspace, notably for test code.  Add a command line suboption to
the existing semihosting-config option group so that you can
explicitly opt in to semihosting from guest userspace with
 -semihosting-config userspace=on

(There is no equivalent option for the user-mode emulator, because
there by definition all code runs in userspace and has access to
semihosting already.)

This commit adds the infrastructure for the command line option and
adds a bool 'is_user' parameter to the function
semihosting_userspace_enabled() that target code can use to check
whether it should be permitting the semihosting call for userspace.
It mechanically makes all the callsites pass 'false', so they
continue checking "is semihosting enabled in general".  Subsequent
commits will make each target that implements semihosting honour the
userspace=on option by passing the correct value and removing
whatever "don't do this for userspace" checking they were doing by
hand.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220822141230.3658237-2-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-09-13 17:18:21 +01:00
Alex Bennée
5af2b0f6ea qemu-options: try and clarify preferred block semantics
Try to correct any confusion about QEMU's Byzantine disk options by
laying out the preferred "modern" options as-per:

 "<danpb> (best:  -device + -blockdev,  2nd obsolete syntax: -device +
     -drive,  3rd obsolete syntax: -drive, 4th obsolete syntax: -hdNN)"

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Cc: qemu-block@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Hanna Reitz <hreitz@redhat.com>
Cc: Thomas Huth <thuth@redhat.com>
Message-Id: <20220822165608.2980552-7-alex.bennee@linaro.org>
2022-08-24 10:14:49 +01:00
Alex Bennée
1235cf7d31 qemu-options: bring the kernel and image options together
How to control the booting of QEMU is often a source of confusion for
users. Bring the options that control this together in the manual
pages and add some verbiage to describe when each option is
appropriate. This attempts to codify some of the knowledge expressed
in:

  https://stackoverflow.com/questions/58420670/qemu-bios-vs-kernel-vs-device-loader-file/58434837#58434837

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20220725140520.515340-14-alex.bennee@linaro.org>
2022-07-29 09:48:01 +01:00
Ilya Leoshkevich
0882caf4d6 qapi: Add exit-failure PanicAction
Currently QEMU exits with code 0 on both panic an shutdown. For tests
it is useful to return 1 on panic, so that it counts as a test
failure.

Introduce a new exit-failure PanicAction that makes main() return
EXIT_FAILURE. Tests can use -action panic=exit-failure option to
activate this behavior.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20220725223746.227063-2-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2022-07-29 09:48:01 +01:00
Felix xq Queißner
c34a933802 gtk: Add show_tabs=on|off command line option.
The patch adds "show_tabs" command line option for GTK ui similar to
"grab_on_hover". This option allows tabbed view mode to not have to be
enabled by hand at each start of the VM.

Signed-off-by: Felix "xq" Queißner <xq@random-projects.net>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220712133753.18937-1-xq@random-projects.net>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2022-07-19 14:36:42 +02:00
Jonathan Cameron
03b39fcf64 hw/cxl: Make the CXL fixed memory window setup a machine parameter.
Paolo Bonzini requested this change to simplify the ongoing
effort to allow machine setup entirely via RPC.

Includes shortening the command line form cxl-fixed-memory-window
to cxl-fmw as the command lines are extremely long even with this
change.

The json change is needed to ensure that there is
a CXLFixedMemoryWindowOptionsList even though the actual
element in the json is never used. Similar to existing
SgxEpcProperties.

Update qemu-options.hx to reflect that this is now a -machine
parameter.  The bulk of -M / -machine parameters are documented
under machine, so use that in preference to M.

Update cxl-test and bios-tables-test to reflect new parameters.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Message-Id: <20220608145440.26106-2-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-06-09 19:32:49 -04:00
Thomas Huth
707d93d4ab ui: Remove deprecated options "-sdl" and "-curses"
We have "-sdl" and "-curses", but no "-gtk" and no "-cocoa" ...
these old-style options are rather confusing than helpful nowadays.
Now that the deprecation period is over, let's remove them, so we
get a cleaner interface (where "-display" is the only way to select
the user interface).

Message-Id: <20220519155625.1414365-4-thuth@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-06-03 08:03:28 +02:00
Thomas Huth
a743d60bca ui: Remove deprecated parameters of the "-display sdl" option
Dropping these deprecated parameters simplifies further refactoring
(e.g. QAPIfication is easier without underscores in the name).

Message-Id: <20220519155625.1414365-2-thuth@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-06-03 08:03:28 +02:00
Vladislav Yaroshchuk
b0290db12d net/vmnet: update qemu-options.hx
Update qemu-options.hx to support vmnet networking backend.

Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Tested-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Signed-off-by: Vladislav Yaroshchuk <Vladislav.Yaroshchuk@jetbrains.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2022-05-17 16:48:23 +08:00
Richard Henderson
eec398119f virtio,pc,pci: fixes,cleanups,features
most of CXL support
 fixes, cleanups all over the place
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_upstream' of git://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

virtio,pc,pci: fixes,cleanups,features

most of CXL support
fixes, cleanups all over the place

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

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* tag 'for_upstream' of git://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (86 commits)
  vhost-user-scsi: avoid unlink(NULL) with fd passing
  virtio-net: don't handle mq request in userspace handler for vhost-vdpa
  vhost-vdpa: change name and polarity for vhost_vdpa_one_time_request()
  vhost-vdpa: backend feature should set only once
  vhost-net: fix improper cleanup in vhost_net_start
  vhost-vdpa: fix improper cleanup in net_init_vhost_vdpa
  virtio-net: align ctrl_vq index for non-mq guest for vhost_vdpa
  virtio-net: setup vhost_dev and notifiers for cvq only when feature is negotiated
  hw/i386/amd_iommu: Fix IOMMU event log encoding errors
  hw/i386: Make pic a property of common x86 base machine type
  hw/i386: Make pit a property of common x86 base machine type
  include/hw/pci/pcie_host: Correct PCIE_MMCFG_SIZE_MAX
  include/hw/pci/pcie_host: Correct PCIE_MMCFG_BUS_MASK
  docs/vhost-user: Clarifications for VHOST_USER_ADD/REM_MEM_REG
  vhost-user: more master/slave things
  virtio: add vhost support for virtio devices
  virtio: drop name parameter for virtio_init()
  virtio/vhost-user: dynamically assign VhostUserHostNotifiers
  hw/virtio/vhost-user: don't suppress F_CONFIG when supported
  include/hw: start documenting the vhost API
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-05-16 16:31:01 -07:00
Paolo Bonzini
039a68373c introduce -audio as a replacement for -soundhw
-audio is used like "-audio pa,model=sb16".  It is almost as simple as
-soundhw, but it reuses the -audiodev parsing machinery and attaches an
audiodev to the newly-created device.  The main 'feature' is that
it knows about adding the codec device for model=intel-hda, and adding
the audiodev to the codec device.

In the future, it could be extended to support default models or
builtin devices, just like -nic, or even a default backend.  For now,
keep it simple.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-14 12:33:44 +02:00
Jonathan Cameron
aadfe32091 hw/cxl/host: Add support for CXL Fixed Memory Windows.
The concept of these is introduced in [1] in terms of the
description the CEDT ACPI table. The principal is more general.
Unlike once traffic hits the CXL root bridges, the host system
memory address routing is implementation defined and effectively
static once observable by standard / generic system software.
Each CXL Fixed Memory Windows (CFMW) is a region of PA space
which has fixed system dependent routing configured so that
accesses can be routed to the CXL devices below a set of target
root bridges. The accesses may be interleaved across multiple
root bridges.

For QEMU we could have fully specified these regions in terms
of a base PA + size, but as the absolute address does not matter
it is simpler to let individual platforms place the memory regions.

ExampleS:
-cxl-fixed-memory-window targets.0=cxl.0,size=128G
-cxl-fixed-memory-window targets.0=cxl.1,size=128G
-cxl-fixed-memory-window targets.0=cxl0,targets.1=cxl.1,size=256G,interleave-granularity=2k

Specifies
* 2x 128G regions not interleaved across root bridges, one for each of
  the root bridges with ids cxl.0 and cxl.1
* 256G region interleaved across root bridges with ids cxl.0 and cxl.1
with a 2k interleave granularity.

When system software enumerates the devices below a given root bridge
it can then decide which CFMW to use. If non interleave is desired
(or possible) it can use the appropriate CFMW for the root bridge in
question.  If there are suitable devices to interleave across the
two root bridges then it may use the 3rd CFMS.

A number of other designs were considered but the following constraints
made it hard to adapt existing QEMU approaches to this particular problem.
1) The size must be known before a specific architecture / board brings
   up it's PA memory map.  We need to set up an appropriate region.
2) Using links to the host bridges provides a clean command line interface
   but these links cannot be established until command line devices have
   been added.

Hence the two step process used here of first establishing the size,
interleave-ways and granularity + caching the ids of the host bridges
and then, once available finding the actual host bridges so they can
be used later to support interleave decoding.

[1] CXL 2.0 ECN: CEDT CFMWS & QTG DSM (computeexpresslink.org / specifications)

Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Acked-by: Markus Armbruster <armbru@redhat.com> # QAPI Schema
Message-Id: <20220429144110.25167-28-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 07:57:26 -04:00
Thomas Huth
eeb3647cbc qemu-options: Limit the -xen options to x86 and arm
The Xen hypervisor is only available on x86 and arm - thus let's
limit the related options to these targets.

Message-Id: <20220427133156.344418-1-thuth@redhat.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-05-09 08:21:14 +02:00
Thomas Huth
21abf010bb qemu-options: Limit the -enable-kvm option to the targets that support it
There is no need to present the user with -enable-kvm if there
is no support for KVM on the corresponding target.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220427134906.348118-1-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-28 08:52:22 +02:00
Paolo Bonzini
e960a7ee46 remove -writeconfig
Like -set and -readconfig, it would not really be too hard to
extend -writeconfig to parsing mechanisms other than QemuOpts.
However, the uses of -writeconfig are substantially more
limited, as it is generally easier to write the configuration
by hand in the first place.  In addition, -writeconfig does
not even try to detect cases where it prints incorrect
syntax (for example if values have a quote in them, since
qemu_config_parse does not support any kind of escaping.
Just remove it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414145721.326866-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-28 08:51:56 +02:00
Daniel P. Berrangé
c6b310b37c softmmu: remove deprecated --enable-fips option
Users requiring FIPS support must build QEMU with either the libgcrypt
or gnutls libraries as the crytography backend.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2022-04-26 16:12:25 +01:00
Marc-André Lureau
5324e3e958 qemu-options: define -spice only #ifdef CONFIG_SPICE
Fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=1982600

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2022-03-22 14:39:06 +04:00
Gustavo Noronha Silva
4797adce5f ui/cocoa: add option to swap Option and Command
On Mac OS X the Option key maps to Alt and Command to Super/Meta. This change
swaps them around so that Alt is the key closer to the space bar and Meta/Super
is between Control and Alt, like on non-Mac keyboards.

It is a cocoa display option, disabled by default.

Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Gustavo Noronha Silva <gustavo@noronha.dev.br>
Message-Id: <20210713213200.2547-3-gustavo@noronha.dev.br>
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20220306121119.45631-3-akihiko.odaki@gmail.com>
Reviewed-by: Will Cohen <wwcohen@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-03-15 13:36:33 +01:00
Gustavo Noronha Silva
f844cdb997 ui/cocoa: capture all keys and combos when mouse is grabbed
Applications such as Gnome may use Alt-Tab and Super-Tab for different
purposes, some use Ctrl-arrows so we want to allow qemu to handle
everything when it captures the mouse/keyboard.

However, Mac OS handles some combos like Command-Tab and Ctrl-arrows
at an earlier part of the event handling chain, not letting qemu see it.

We add a global Event Tap that allows qemu to see all events when the
mouse is grabbed. Note that this requires additional permissions.

See:

https://developer.apple.com/documentation/coregraphics/1454426-cgeventtapcreate?language=objc#discussion
https://support.apple.com/en-in/guide/mac-help/mh32356/mac

Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Gustavo Noronha Silva <gustavo@noronha.dev.br>
Message-Id: <20210713213200.2547-2-gustavo@noronha.dev.br>
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20220306121119.45631-2-akihiko.odaki@gmail.com>
Reviewed-by: Will Cohen <wwcohen@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-03-15 13:36:33 +01:00
Carwyn Ellis
48941a52c2 ui/cocoa: add option to disable left-command forwarding to guest
When switching between guest and host on a Mac using command-tab the
command key is sent to the guest which can trigger functionality in the
guest OS. Specifying left-command-key=off disables forwarding this key
to the guest. Defaults to enabled.

Also updated the cocoa display documentation to reference the new
left-command-key option along with the existing show-cursor option.

Signed-off-by: Carwyn Ellis <carwynellis@gmail.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
[PMD: Set QAPI structure @since tag to 7.0]
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-03-15 13:36:33 +01:00
Patrick Venture
cb5fb04fe6 hw/smbios: Add table 4 parameter, "processor-id"
This parameter is to be used in the processor_id entry in the type 4
table.

This parameter is set as optional and if left will use the values from
the CPU model.

This enables hiding the host information from the guest and allowing AMD
VMs to run pretending to be Intel for some userspace software concerns.

Reviewed-by: Peter Foley <pefoley@google.com>
Reviewed-by: Titus Rwantare <titusr@google.com>
Signed-off-by: Patrick Venture <venture@google.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20220125163118.1011809-1-venture@google.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-06 05:28:55 -05:00
Laurent Vivier
35aab30326 qemu-options: fix incorrect description for '-drive index='
qemu-options.hx contains grammar that a native English-speaking
person would never use.

Replace "This option defines where is connected the drive" by
"This option defines where the drive is connected".

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/853
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220202143422.912070-1-lvivier@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-02-22 17:15:21 +01:00
Yanan Wang
d55c316f91 hw/arm/virt: Support CPU cluster on ARM virt machine
ARM64 machines like Kunpeng Family Server Chips have a level
of hardware topology in which a group of CPU cores share L3
cache tag or L2 cache. For example, Kunpeng 920 typically
has 6 or 8 clusters in each NUMA node (also represent range
of CPU die), and each cluster has 4 CPU cores. All clusters
share L3 cache data, but CPU cores in each cluster share a
local L3 tag.

Running a guest kernel with Cluster-Aware Scheduling on the
Hosts which have physical clusters, if we can design a vCPU
topology with cluster level for guest kernel and then have
a dedicated vCPU pinning, the guest will gain scheduling
performance improvement from cache affinity of CPU cluster.

So let's enable the support for this new parameter on ARM
virt machines. After this patch, we can define a 4-level
CPU hierarchy like: cpus=*,maxcpus=*,sockets=*,clusters=*,
cores=*,threads=*.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-id: 20220107083232.16256-2-wangyanan55@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-01-20 11:47:52 +00:00
Thomas Huth
fe86fe237c qemu-options: Remove the deprecated -no-quit option
This option was just a wrapper around the -display ...,window-close=off
parameter, and the name "no-quit" is rather confusing compared to
"window-close" (since there are still other means to quit the emulator),
so let's remove this now.

Message-Id: <20211215082417.180735-1-thuth@redhat.com>
Acked-by: Michal Prívozník <mprivozn@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-01-05 11:10:13 +01:00
Yanan Wang
864c3b5c32 hw/core/machine: Introduce CPU cluster topology support
The new Cluster-Aware Scheduling support has landed in Linux 5.16,
which has been proved to benefit the scheduling performance (e.g.
load balance and wake_affine strategy) on both x86_64 and AArch64.

So now in Linux 5.16 we have four-level arch-neutral CPU topology
definition like below and a new scheduler level for clusters.
struct cpu_topology {
    int thread_id;
    int core_id;
    int cluster_id;
    int package_id;
    int llc_id;
    cpumask_t thread_sibling;
    cpumask_t core_sibling;
    cpumask_t cluster_sibling;
    cpumask_t llc_sibling;
}

A cluster generally means a group of CPU cores which share L2 cache
or other mid-level resources, and it is the shared resources that
is used to improve scheduler's behavior. From the point of view of
the size range, it's between CPU die and CPU core. For example, on
some ARM64 Kunpeng servers, we have 6 clusters in each NUMA node,
and 4 CPU cores in each cluster. The 4 CPU cores share a separate
L2 cache and a L3 cache tag, which brings cache affinity advantage.

In virtualization, on the Hosts which have pClusters (physical
clusters), if we can design a vCPU topology with cluster level for
guest kernel and have a dedicated vCPU pinning. A Cluster-Aware
Guest kernel can also make use of the cache affinity of CPU clusters
to gain similar scheduling performance.

This patch adds infrastructure for CPU cluster level topology
configuration and parsing, so that the user can specify cluster
parameter if their machines support it.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Message-Id: <20211228092221.21068-3-wangyanan55@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[PMD: Added '(since 7.0)' to @clusters in qapi/machine.json]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-12-31 13:42:39 +01:00
Yanan Wang
0d87178523 qemu-options: Improve readability of SMP related Docs
We have a description in qemu-options.hx for each CPU topology
parameter to explain what it exactly means, and also an extra
declaration for the target-specific one, e.g. "for PC only"
when describing "dies", and "for PC, it's on one die" when
describing "cores".

Now we are going to introduce one more non-generic parameter
"clusters", it will make the Doc less readable and  if we still
continue to use the legacy way to describe it.

So let's at first make two tweaks of the Docs to improve the
readability and also scalability:
1) In the -help text: Delete the extra specific declaration and
   describe each topology parameter level by level. Then add a
   note to declare that different machines may support different
   subsets and the actual meaning of the supported parameters
   will vary accordingly.
2) In the rST text: List all the sub-hierarchies currently
   supported in QEMU, and correspondingly give an example of
   -smp configuration for each of them.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211228092221.21068-2-wangyanan55@huawei.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-12-31 13:42:34 +01:00
Marc-André Lureau
739362d420 audio: add "dbus" audio backend
Add a new -audio backend that accepts D-Bus clients/listeners to handle
playback & recording, to be exported via the -display dbus.

Example usage:
-audiodev dbus,in.mixing-engine=off,out.mixing-engine=off,id=dbus
-display dbus,audiodev=dbus

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
2021-12-21 10:50:22 +04:00
Marc-André Lureau
99997823bb ui/dbus: add p2p=on/off option
Add an option to use direct connections instead of via the bus. Clients
are accepted with QMP add_client.

This allows to provide the D-Bus display without a bus. It also
simplifies the testing setup (some CI have issues to setup a D-Bus bus
in a container).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
2021-12-21 10:50:22 +04:00
Marc-André Lureau
142ca628a7 ui: add a D-Bus display backend
The "dbus" display backend exports the QEMU consoles and other
UI-related interfaces over D-Bus.

By default, the connection is established on the session bus, but you
can specify a different bus with the "addr" option.

The backend takes the "org.qemu" service name, while still allowing
further instances to queue on the same name (so you can lookup all the
available instances too). It accepts any number of clients at this
point, although this is expected to evolve with options to restrict
clients, or only accept p2p via fd passing.

The interface is intentionally very close to the internal QEMU API,
and can be introspected or interacted with busctl/dfeet etc:

$ ./qemu-system-x86_64 -name MyVM -display dbus
$ busctl --user introspect org.qemu /org/qemu/Display1/Console_0

org.qemu.Display1.Console           interface -         -               -
.RegisterListener                   method    h         -               -
.SetUIInfo                          method    qqiiuu    -               -
.DeviceAddress                      property  s         "pci/0000/01.0" emits-change
.Head                               property  u         0               emits-change
.Height                             property  u         480             emits-change
.Label                              property  s         "VGA"           emits-change
.Type                               property  s         "Graphic"       emits-change
.Width                              property  u         640             emits-change
[...]

See the interfaces XML source file and Sphinx docs for the generated API
documentations.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
2021-12-21 10:50:22 +04:00
Yang Zhong
1105812382 numa: Enable numa for SGX EPC sections
The basic SGX did not enable numa for SGX EPC sections, which
result in all EPC sections located in numa node 0. This patch
enable SGX numa function in the guest and the EPC section can
work with RAM as one numa node.

The Guest kernel related log:
[    0.009981] ACPI: SRAT: Node 0 PXM 0 [mem 0x180000000-0x183ffffff]
[    0.009982] ACPI: SRAT: Node 1 PXM 1 [mem 0x184000000-0x185bfffff]
The SRAT table can normally show SGX EPC sections menory info in different
numa nodes.

The SGX EPC numa related command:
 ......
 -m 4G,maxmem=20G \
 -smp sockets=2,cores=2 \
 -cpu host,+sgx-provisionkey \
 -object memory-backend-ram,size=2G,host-nodes=0,policy=bind,id=node0 \
 -object memory-backend-epc,id=mem0,size=64M,prealloc=on,host-nodes=0,policy=bind \
 -numa node,nodeid=0,cpus=0-1,memdev=node0 \
 -object memory-backend-ram,size=2G,host-nodes=1,policy=bind,id=node1 \
 -object memory-backend-epc,id=mem1,size=28M,prealloc=on,host-nodes=1,policy=bind \
 -numa node,nodeid=1,cpus=2-3,memdev=node1 \
 -M sgx-epc.0.memdev=mem0,sgx-epc.0.node=0,sgx-epc.1.memdev=mem1,sgx-epc.1.node=1 \
 ......

Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20211101162009.62161-2-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-10 09:47:18 +01:00
Dov Murik
55cdf56641 qapi/qom,target/i386: sev-guest: Introduce kernel-hashes=on|off option
Introduce new boolean 'kernel-hashes' option on the sev-guest object.
It will be used to to decide whether to add the hashes of
kernel/initrd/cmdline to SEV guest memory when booting with -kernel.
The default value is 'off'.

Signed-off-by: Dov Murik <dovmurik@linux.ibm.com>
Acked-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-11-18 11:07:44 +00:00
John Snow
450e0f28a4 docs: remove non-reference uses of single backticks
The single backtick markup in ReST is the "default role". Currently,
Sphinx's default role is called "content". Sphinx suggests you can use
the "Any" role instead to turn any single-backtick enclosed item into a
cross-reference.

This is useful for things like autodoc for Python docstrings, where it's
often nicer to reference other types with `foo` instead of the more
laborious :py:meth:`foo`. It's also useful in multi-domain cases to
easily reference definitions from other Sphinx domains, such as
referencing C code definitions from outside of kerneldoc comments.

Before we do that, though, we'll need to turn all existing usages of the
"content" role to inline verbatim markup wherever it does not correctly
resolve into a cross-refernece by using double backticks instead.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20211004215238.1523082-2-jsnow@redhat.com>
2021-11-08 12:27:23 +04:00
Markus Armbruster
57df0dff1a qapi: Extend -compat to set policy for unstable interfaces
New option parameters unstable-input and unstable-output set policy
for unstable interfaces just like deprecated-input and
deprecated-output set policy for deprecated interfaces (see commit
6dd75472d5 "qemu-options: New -compat to set policy for deprecated
interfaces").  This is intended for testing users of the management
interfaces.  It is experimental.

For now, this covers only syntactic aspects of QMP, i.e. stuff tagged
with feature 'unstable'.  We may want to extend it to cover semantic
aspects, or the command line.

Note that there is no good way for management application to detect
presence of these new option parameters: they are not visible output
of query-qmp-schema or query-command-line-options.  Tolerable, because
it's meant for testing.  If running with -compat fails, skip the test.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-10-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Doc comments fixed up]
2021-10-29 21:28:01 +02:00
Yanan Wang
848dd26928 qemu-options: Add missing "sockets=2, maxcpus=2" to CLI "-smp 2"
There is one numa config example in qemu-options.hx currently
using "-smp 2" and assuming that there will be 2 sockets and
2 cpus totally. However now the actual calculation logic of
missing sockets and cores is not immutable and is considered
liable to change. Although we will get maxcpus=2 finally based
on current parser, it's always stable to specify it explicitly.

So "-smp 2,sockets=2,maxcpus=2" will be optimal when we expect
multiple sockets and 2 cpus totally.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20210928121134.21064-3-wangyanan55@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-10-04 09:47:26 +02:00
Yanan Wang
553dc36b38 qemu-options: Tweak [, maxcpus=cpus] to [, maxcpus=maxcpus]
In qemu-option.hx, there is "-smp [[cpus=]n][,maxcpus=cpus]..." in the
DEF part, and "-smp [[cpus=]n][,maxcpus=maxcpus]..." in the RST part.
Obviously the later is right, let's fix the previous one.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20210928121134.21064-2-wangyanan55@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-10-04 09:47:26 +02:00
Markus Armbruster
ba858d1fad qemu-options: -chardev reconnect=seconds duplicated in help, tidy up
Fixes: 5dd1f02b4b
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210928071449.1416022-1-armbru@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-10-04 09:47:26 +02:00
Yanan Wang
4a0af2930a machine: Prefer cores over sockets in smp parsing since 6.2
In the real SMP hardware topology world, it's much more likely that
we have high cores-per-socket counts and few sockets totally. While
the current preference of sockets over cores in smp parsing results
in a virtual cpu topology with low cores-per-sockets counts and a
large number of sockets, which is just contrary to the real world.

Given that it is better to make the virtual cpu topology be more
reflective of the real world and also for the sake of compatibility,
we start to prefer cores over sockets over threads in smp parsing
since machine type 6.2 for different arches.

In this patch, a boolean "smp_prefer_sockets" is added, and we only
enable the old preference on older machines and enable the new one
since type 6.2 for all arches by using the machine compat mechanism.

Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-10-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 15:28:16 +02:00
Yanan Wang
7d8c5a3962 machine: Set the value of cpus to match maxcpus if it's omitted
Currently we directly calculate the omitted cpus based on the given
incomplete collection of parameters. This makes some cmdlines like:
  -smp maxcpus=16
  -smp sockets=2,maxcpus=16
  -smp sockets=2,dies=2,maxcpus=16
  -smp sockets=2,cores=4,maxcpus=16
not work. We should probably set the value of cpus to match maxcpus
if it's omitted, which will make above configs start to work.

So the calculation logic of cpus/maxcpus after this patch will be:
When both maxcpus and cpus are omitted, maxcpus will be calculated
from the given parameters and cpus will be set equal to maxcpus.
When only one of maxcpus and cpus is given then the omitted one
will be set to its counterpart's value. Both maxcpus and cpus may
be specified, but maxcpus must be equal to or greater than cpus.

Note: change in this patch won't affect any existing working cmdlines
but allows more incomplete configs to be valid.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-6-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 15:27:56 +02:00
Yanan Wang
c2511b1632 machine: Deprecate "parameter=0" SMP configurations
In the SMP configuration, we should either provide a topology
parameter with a reasonable value (greater than zero) or just
omit it and QEMU will compute the missing value.

The users shouldn't provide a configuration with any parameter
of it specified as zero (e.g. -smp 8,sockets=0) which could
possibly cause unexpected results in the -smp parsing. So we
deprecate this kind of configurations since 6.2 by adding the
explicit sanity check.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-3-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 15:27:56 +02:00
Sean Christopherson
dfce81f1b9 vl: Add sgx compound properties to expose SGX EPC sections to guest
Because SGX EPC is enumerated through CPUID, EPC "devices" need to be
realized prior to realizing the vCPUs themselves, i.e. long before
generic devices are parsed and realized.  From a virtualization
perspective, the CPUID aspect also means that EPC sections cannot be
hotplugged without paravirtualizing the guest kernel (hardware does
not support hotplugging as EPC sections must be locked down during
pre-boot to provide EPC's security properties).

So even though EPC sections could be realized through the generic
-devices command, they need to be created much earlier for them to
actually be usable by the guest.  Place all EPC sections in a
contiguous block, somewhat arbitrarily starting after RAM above 4g.
Ensuring EPC is in a contiguous region simplifies calculations, e.g.
device memory base, PCI hole, etc..., allows dynamic calculation of the
total EPC size, e.g. exposing EPC to guests does not require -maxmem,
and last but not least allows all of EPC to be enumerated in a single
ACPI entry, which is expected by some kernels, e.g. Windows 7 and 8.

The new compound properties command for sgx like below:
 ......
 -object memory-backend-epc,id=mem1,size=28M,prealloc=on \
 -object memory-backend-epc,id=mem2,size=10M \
 -M sgx-epc.0.memdev=mem1,sgx-epc.1.memdev=mem2

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20210719112136.57018-6-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-30 14:50:20 +02:00
Thomas Huth
d46156fdcc softmmu/vl: Deprecate the old grab options
The alt_grab and ctrl_grab parameter of the -display sdl option prevent
the QAPIfication of the "sdl" part of the -display option, so we should
eventually remove them. And since this feature is also rather niche anyway,
we should not clutter the top-level option list with these, so let's
also deprecate the "-alt-grab" and the "-ctrl-grab" options while we're
at it.

Once the deprecation period of "alt_grab" and "ctrl_grab" is over, we
then can finally switch the -display sdl option to use QAPI internally,
too.

Message-Id: <20210825092023.81396-3-thuth@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-09-06 10:00:14 +02:00
Thomas Huth
8e8e844be4 softmmu/vl: Add a "grab-mod" parameter to the -display sdl option
The -display sdl option is not using QAPI internally yet, and uses hand-
crafted parsing instead (see parse_display() in vl.c), which is quite
ugly, since most of the other code is using the QAPIfied DisplayOption
already. Unfortunately, the "alt_grab" and "ctrl_grab" use underscores in
their names which has recently been forbidden in new QAPI code, so
a straight conversion is not possible. While we could add some exceptions
to the QAPI schema parser for this, the way these parameters have been
designed was maybe a bad idea anyway: First, it's not possible to enable
both parameters at the same time, thus instead of two boolean parameters
it would be better to have only one multi-choice parameter instead.
Second, the naming is also somewhat unfortunate since the "alt_grab"
parameter is not about the ALT key, but rather about the left SHIFT key
that has to be used additionally when the parameter is enabled.

So instead of trying to QAPIfy "alt_grab" and "ctrl_grab", let's rather
introduce an alternative to these parameters instead, a new parameter
called "grab-mod" which can either be set to "lshift-lctrl-lalt" or to
"rctrl". In case we ever want to support additional modes later, we can
then also simply extend the list of supported strings here.

Message-Id: <20210825092023.81396-2-thuth@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-09-06 10:00:14 +02:00
Mahmoud Mandour
3a445acb49 plugins: allow plugin arguments to be passed directly
Passing arguments to plugins had to be done through "arg=<argname>".
This is redundant and introduces confusion especially when the argument
has a name and value (e.g. `-plugin plugin_name,arg="argname=argvalue"`).

This allows passing plugin arguments directly e.g:

    `-plugin plugin_name,argname=argvalue`

For now, passing arguments through "arg=" is still supports but outputs
a deprecation warning.

Also, this commit makes boolean arguments passed to plugins in the
`argname=on|off` form instead of the deprecated short-boolean form.

Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210730135817.17816-2-ma.mandourr@gmail.com>
2021-09-02 11:29:34 +01:00
Peter Maydell
953558291e qemu-options.hx: Fix formatting of -machine memory-backend option
The documentation of the -machine memory-backend has some minor
formatting errors:
 * Misindentation of the initial line meant that the whole option
   section is incorrectly indented in the HTML output compared to
   the other -machine options
 * The examples weren't indented, which meant that they were formatted
   as plain run-on text including outputting the "::" as text.
 * The a) b) list has no rst-format markup so it is rendered as
   a single run-on paragraph

Fix the formatting.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-id: 20210719105257.3599-1-peter.maydell@linaro.org
2021-07-27 10:57:39 +01:00
Stefano Garzarella
1793ad0247 iothread: add aio-max-batch parameter
The `aio-max-batch` parameter will be propagated to AIO engines
and it will be used to control the maximum number of queued requests.

When there are in queue a number of requests equal to `aio-max-batch`,
the engine invokes the system call to forward the requests to the kernel.

This parameter allows us to control the maximum batch size to reduce
the latency that requests might accumulate while queued in the AIO
engine queue.

If `aio-max-batch` is equal to 0 (default value), the AIO engine will
use its default maximum batch size value.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20210721094211.69853-3-sgarzare@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-07-21 13:47:50 +01:00
Peter Xu
7395b3e3e7 docs: Add '-device intel-iommu' entry
The parameters of intel-iommu device are non-trivial to understand.  Add an
entry for it so that people can reference to it when using.

There're actually a few more options there, but I hide them explicitly because
they shouldn't be used by normal QEMU users.

Cc: Chao Yang <chayang@redhat.com>
Cc: Lei Yang <leiyang@redhat.com>
Cc: Jing Zhao <jinzhao@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210707154114.197580-1-peterx@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-07-16 11:10:45 -04:00
Daniel P. Berrangé
80d7835749 qemu-options: rewrite help for -smp options
The -smp option help is peculiarly specific about mentioning the CPU
upper limits, but these are wrong. The "PC" target has varying max
CPU counts depending on the machine type picked. Notes about guest
OS limits are inappropriate for QEMU docs. There are way too many
machine types for it to be practical to mention actual limits, and
some limits are even modified by downstream distribtions. Thus it
is better to remove the specific limits entirely.

The CPU topology reporting is also not neccessarily specific to the
PC platform and descriptions around the rules of usage are somewhat
terse. Expand this information with some examples to show effects
of defaulting.

Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-07-14 14:16:35 +01:00
Daniel P. Berrangé
b9361bdc1f qemu-options: tweak to show that CPU count is optional
The initial CPU count number is not required, if any of the topology
options are given, since it can be computed.

Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Yanan Wang <wangyanan55@huawei.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-07-14 14:16:33 +01:00