Original Xbox Emulator for Windows, macOS, and Linux (Active Development)
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Daniel P. Berrangé d96aa5db4f char: fix logging when chardev write fails
The qemu_chr_write_buffer() method sends data to the chardev backend for
writing, and then also writes to the log file. In case the chardev
backend only writes part of the data buffer, we need to make sure we
only log the same subset. qemu_chr_write_buffer() will be invoked again
later to write the rest of the buffer.

In the case the chardev backend returns an error though, no further
attempts to likely to be made to write the data. We must therefore write
the entire buffer to the log immediately.

An example where this is important is with the socket backend. This will
return -1 for all writes if no client is currently connected. We still
wish to write data to the log file when no client is present though.
This used to work because the chardev would return "len" to pretend it
had written all data when no client is connected, but this changed to
return an error in

  commit 271094474b
  Author: Dima Stepanov <dimastep@yandex-team.ru>
  Date: Thu May 28 12:11:18 2020 +0300

    char-socket: return -1 in case of disconnect during tcp_chr_write

and this broke the logging, resulting in all data being discarded when
no client is present.

Fixes: https://bugs.launchpad.net/qemu/+bug/1893691
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
.github
.gitlab-ci.d gitlab-ci: Add cross-compiling build tests 2020-09-07 12:34:17 +02:00
accel exec: Remove MemoryRegion::global_locking field 2020-09-30 19:11:36 +02:00
audio Pull request 2020-09-24 18:48:45 +01:00
authz qom: Remove ParentClassType argument from OBJECT_DECLARE_SIMPLE_TYPE 2020-09-18 14:12:32 -04:00
backends cryptodev-backend: Register "chardev" as class property 2020-09-22 16:46:09 -04:00
block qapi: Restrict query-uuid command to machine code 2020-09-29 15:41:35 +02:00
bsd-user meson: bsd-user 2020-08-21 06:30:38 -04:00
capstone@22ead3e0bf
chardev char: fix logging when chardev write fails 2020-09-30 19:11:36 +02:00
contrib libvhost-user: return on error in vu_log_queue_fill() 2020-09-29 03:06:12 -04:00
crypto qom: Remove ParentClassType argument from OBJECT_DECLARE_SIMPLE_TYPE 2020-09-18 14:12:32 -04:00
default-configs hw/arm: Add two NPCM7xx-based machines 2020-09-14 14:24:58 +01:00
disas disas/: fix some comment spelling errors 2020-09-17 20:40:08 +02:00
docs smp: drop support for deprecated (invalid topologies) 2020-09-30 19:11:36 +02:00
dtc@85e5d83984
dump qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
fpu softfloat: Define misc operations for bfloat16 2020-08-28 10:48:07 -07:00
fsdev Pull request trivial patches 20200919 2020-09-22 15:42:23 +01:00
gdb-xml target/avr: CPU class: Add GDB support 2020-07-10 17:58:32 +02:00
hw hw/i386/q35: Remove unreachable Xen code on Q35 machine 2020-09-30 19:11:36 +02:00
include exec: Remove MemoryRegion::global_locking field 2020-09-30 19:11:36 +02:00
io qom: Remove ParentClassType argument from OBJECT_DECLARE_SIMPLE_TYPE 2020-09-18 14:12:32 -04:00
libdecnumber qemu/: fix some comment spelling errors 2020-09-17 20:35:43 +02:00
linux-headers linux headers: sync to 5.9-rc4 2020-09-29 02:14:29 -04:00
linux-user qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
meson@68ed748f84 meson: bump submodule to 0.55.1 2020-09-01 01:51:51 -04:00
migration Migration: Revert one patch for 068 fix 2020-09-29 10:29:46 +01:00
monitor qapi: Extract PCI commands to 'pci.json' 2020-09-29 15:41:36 +02:00
nbd nbd: Use CAF when looking for dirty bitmap 2020-09-07 12:31:31 +02:00
net net: relocate paths to helpers and scripts 2020-09-30 19:11:36 +02:00
pc-bios meson: fix installation of keymaps 2020-09-30 19:11:36 +02:00
plugins meson: link emulators without Makefile.target 2020-08-21 06:30:40 -04:00
po meson: convert po/ 2020-08-21 06:30:45 -04:00
python/qemu python/qemu: Change ConsoleSocket to optionally drain socket. 2020-07-27 09:41:56 +01:00
qapi qapi: Use rST markup for literal blocks 2020-09-29 17:55:39 +02:00
qga qga: relocate path to default configuration and hook 2020-09-30 19:11:36 +02:00
qobject qemu/: fix some comment spelling errors 2020-09-17 20:35:43 +02:00
qom Pull request 2020-09-24 18:48:45 +01:00
replay meson: convert replay directory to Meson 2020-08-21 06:30:23 -04:00
roms seabios: add microvm config, update build rules 2020-09-17 14:16:19 +02:00
scripts checkpatch: avoid error on cover letter files 2020-09-30 19:11:36 +02:00
scsi qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
slirp@ce94eba204 slirp: update to latest stable-4.2 branch 2020-07-28 18:27:59 +04:00
softmmu exec: Remove MemoryRegion::global_locking field 2020-09-30 19:11:36 +02:00
storage-daemon docs/interop: Convert qemu-qmp-ref to rST 2020-09-29 17:55:39 +02:00
stubs qapi: Restrict query-uuid command to machine code 2020-09-29 15:41:35 +02:00
target i386/cpu: Clear FEAT_XSAVE_COMP_{LO,HI} when XSAVE is not available 2020-09-30 19:09:20 +02:00
tcg qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
tests tests/tcg: reinstate or replace desired parts of rules.mak 2020-09-30 19:11:36 +02:00
tools virtiofsd: Add -o allow_direct_io|no_allow_direct_io options 2020-09-25 12:45:58 +01:00
trace meson: clean up build_by_default 2020-09-30 19:09:19 +02:00
ui ui: relocate paths to icons and translations 2020-09-30 19:11:36 +02:00
util module: relocate path to modules 2020-09-30 19:11:36 +02:00
.cirrus.yml cirrus: Building freebsd in a single shot 2020-09-16 12:15:07 +02:00
.dir-locals.el
.editorconfig meson: rename included C source files to .c.inc 2020-08-21 06:18:30 -04:00
.exrc
.gdbinit
.gitignore Add *.pyc back to the .gitignore file 2020-09-23 19:09:56 +02:00
.gitlab-ci.yml configure: add [lm32|unicore32]-softmmu to deprecation logic 2020-09-16 10:07:01 +01:00
.gitmodules gitmodules: add qemu.org vbootrom submodule 2020-09-23 13:44:59 +01:00
.gitpublish
.mailmap mailmap: Add entry for Greg Kurz 2020-09-01 11:13:02 +02:00
.patchew.yml
.readthedocs.yml
.shippable.yml configure: add [lm32|unicore32]-softmmu to deprecation logic 2020-09-16 10:07:01 +01:00
.travis.yml Remove texinfo dependency from docker and CI configs 2020-09-29 17:55:39 +02:00
block.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
blockdev-nbd.c
blockdev.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
blockjob.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
bootdevice.c error: Eliminate error_propagate() manually 2020-07-10 15:18:08 +02:00
Changelog qemu/: fix some comment spelling errors 2020-09-17 20:35:43 +02:00
CODING_STYLE.rst CODING_STYLE.rst: flesh out our naming conventions. 2020-09-10 10:34:58 +01:00
configure configure: use a platform-neutral prefix 2020-09-30 19:11:36 +02:00
COPYING
COPYING.LIB
cpus-common.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
device_tree.c
disas.c
dma-helpers.c trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
exec-vary.c
exec.c exec: Remove MemoryRegion::global_locking field 2020-09-30 19:11:36 +02:00
gdbstub.c trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
gitdm.config
hmp-commands-info.hx
hmp-commands.hx cphp: remove deprecated cpu-add command(s) 2020-09-29 02:14:30 -04:00
iothread.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
job-qmp.c trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
job.c trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
Kconfig Makefile: simplify MINIKCONF rules 2020-07-10 18:02:21 -04:00
Kconfig.host configure: Fix build dependencies with vhost-vdpa. 2020-09-29 02:15:24 -04:00
LICENSE
MAINTAINERS MAINTAINERS: add Paolo Bonzini as RCU maintainer 2020-09-30 19:09:19 +02:00
Makefile mtest2make: add support for introspected test dependencies 2020-09-30 19:11:36 +02:00
memory_ldst.c.inc meson: rename included C source files to .c.inc 2020-08-21 06:18:30 -04:00
meson_options.txt configure: move cocoa option to Meson 2020-09-30 19:11:36 +02:00
meson.build oss-fuzz: move linker arg to fix coverage-build 2020-09-30 19:11:36 +02:00
module-common.c
os-posix.c vl: relocate paths to data directories 2020-09-30 19:11:36 +02:00
os-win32.c vl: relocate paths to data directories 2020-09-30 19:11:36 +02:00
qdev-monitor.c qdev: Fix device_add DRIVER,help to print to monitor 2020-07-21 17:22:44 +02:00
qemu-bridge-helper.c qemu-bridge-helper: relocate path to default ACL 2020-09-30 19:11:36 +02:00
qemu-edid.c edid: use physical dimensions if available 2020-09-29 10:08:25 +02:00
qemu-img-cmds.hx block/amend: add 'force' option 2020-07-06 08:49:28 +02:00
qemu-img.c bitmaps patches for 2020-09-21 2020-09-23 15:11:38 +01:00
qemu-io-cmds.c block: nbd: Fix convert qcow2 compressed to nbd 2020-07-28 09:54:19 -05:00
qemu-io.c block: add missing socket_init() calls to tools 2020-09-02 16:47:39 -05:00
qemu-keymap.c
qemu-nbd.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
qemu-options-wrapper.h
qemu-options.h
qemu-options.hx qemu-options: document SMBIOS type 11 settings 2020-09-29 03:06:12 -04:00
qemu-seccomp.c seccomp: fix killing of whole process instead of thread 2020-09-15 12:56:26 +02:00
qemu.nsi
qemu.sasl
README.rst
replication.c
replication.h
thunk.c linux-user: Add strace support for printing arguments for ioctls used for terminals and serial lines 2020-08-27 12:29:50 +02:00
tpm.c tpm: Improve help on TPM types when none are available 2020-07-24 12:44:13 -04:00
trace-events trace-events: Fix attribution of trace points to source 2020-09-09 17:17:58 +01:00
VERSION Open 5.2 development tree 2020-08-18 13:44:04 +01:00
version.rc
version.texi.in meson: build texi doc 2020-08-21 06:30:42 -04:00

===========
QEMU README
===========

QEMU is a generic and open source machine & userspace emulator and
virtualizer.

QEMU is capable of emulating a complete machine in software without any
need for hardware virtualization support. By using dynamic translation,
it achieves very good performance. QEMU can also integrate with the Xen
and KVM hypervisors to provide emulated hardware while allowing the
hypervisor to manage the CPU. With hypervisor support, QEMU can achieve
near native performance for CPUs. When QEMU emulates CPUs directly it is
capable of running operating systems made for one machine (e.g. an ARMv7
board) on a different machine (e.g. an x86_64 PC board).

QEMU is also capable of providing userspace API virtualization for Linux
and BSD kernel interfaces. This allows binaries compiled against one
architecture ABI (e.g. the Linux PPC64 ABI) to be run on a host using a
different architecture ABI (e.g. the Linux x86_64 ABI). This does not
involve any hardware emulation, simply CPU and syscall emulation.

QEMU aims to fit into a variety of use cases. It can be invoked directly
by users wishing to have full control over its behaviour and settings.
It also aims to facilitate integration into higher level management
layers, by providing a stable command line interface and monitor API.
It is commonly invoked indirectly via the libvirt library when using
open source applications such as oVirt, OpenStack and virt-manager.

QEMU as a whole is released under the GNU General Public License,
version 2. For full licensing details, consult the LICENSE file.


Building
========

QEMU is multi-platform software intended to be buildable on all modern
Linux platforms, OS-X, Win32 (via the Mingw64 toolchain) and a variety
of other UNIX targets. The simple steps to build QEMU are:


.. code-block:: shell

  mkdir build
  cd build
  ../configure
  make

Additional information can also be found online via the QEMU website:

* `<https://qemu.org/Hosts/Linux>`_
* `<https://qemu.org/Hosts/Mac>`_
* `<https://qemu.org/Hosts/W32>`_


Submitting patches
==================

The QEMU source code is maintained under the GIT version control system.

.. code-block:: shell

   git clone https://git.qemu.org/git/qemu.git

When submitting patches, one common approach is to use 'git
format-patch' and/or 'git send-email' to format & send the mail to the
qemu-devel@nongnu.org mailing list. All patches submitted must contain
a 'Signed-off-by' line from the author. Patches should follow the
guidelines set out in the CODING_STYLE.rst file.

Additional information on submitting patches can be found online via
the QEMU website

* `<https://qemu.org/Contribute/SubmitAPatch>`_
* `<https://qemu.org/Contribute/TrivialPatches>`_

The QEMU website is also maintained under source control.

.. code-block:: shell

  git clone https://git.qemu.org/git/qemu-web.git

* `<https://www.qemu.org/2017/02/04/the-new-qemu-website-is-up/>`_

A 'git-publish' utility was created to make above process less
cumbersome, and is highly recommended for making regular contributions,
or even just for sending consecutive patch series revisions. It also
requires a working 'git send-email' setup, and by default doesn't
automate everything, so you may want to go through the above steps
manually for once.

For installation instructions, please go to

*  `<https://github.com/stefanha/git-publish>`_

The workflow with 'git-publish' is:

.. code-block:: shell

  $ git checkout master -b my-feature
  $ # work on new commits, add your 'Signed-off-by' lines to each
  $ git publish

Your patch series will be sent and tagged as my-feature-v1 if you need to refer
back to it in the future.

Sending v2:

.. code-block:: shell

  $ git checkout my-feature # same topic branch
  $ # making changes to the commits (using 'git rebase', for example)
  $ git publish

Your patch series will be sent with 'v2' tag in the subject and the git tip
will be tagged as my-feature-v2.

Bug reporting
=============

The QEMU project uses Launchpad as its primary upstream bug tracker. Bugs
found when running code built from QEMU git or upstream released sources
should be reported via:

* `<https://bugs.launchpad.net/qemu/>`_

If using QEMU via an operating system vendor pre-built binary package, it
is preferable to report bugs to the vendor's own bug tracker first. If
the bug is also known to affect latest upstream code, it can also be
reported via launchpad.

For additional information on bug reporting consult:

* `<https://qemu.org/Contribute/ReportABug>`_


Contact
=======

The QEMU community can be contacted in a number of ways, with the two
main methods being email and IRC

* `<mailto:qemu-devel@nongnu.org>`_
* `<https://lists.nongnu.org/mailman/listinfo/qemu-devel>`_
* #qemu on irc.oftc.net

Information on additional methods of contacting the community can be
found online via the QEMU website:

* `<https://qemu.org/Contribute/StartHere>`_