@item -machine [type=]@var{name}[,prop=@var{value}[,...]]
@findex -machine
Select the emulated machine by @var{name}. Use @code{-machine help} to list
-available machines. Supported machine properties are:
+available machines.
+
+For architectures which aim to support live migration compatibility
+across releases, each release will introduce a new versioned machine
+type. For example, the 2.8.0 release introduced machine types
+``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures.
+
+To allow live migration of guests from QEMU version 2.8.0, to QEMU
+version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8''
+and ``pc-q35-2.8'' machines too. To allow users live migrating VMs
+to skip multiple intermediate releases when upgrading, new releases
+of QEMU will support machine types from many previous versions.
+
+Supported machine properties are:
@table @option
@item accel=@var{accels1}[:@var{accels2}[:...]]
This is used to enable an accelerator. Depending on the target architecture,
qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img
@end example
-In particular, you can use this to set driver properties for devices which are
-created automatically by the machine model. To create a device which is not
+In particular, you can use this to set driver properties for devices which are
+created automatically by the machine model. To create a device which is not
created automatically and set properties on it, use -@option{device}.
-global @var{driver}.@var{prop}=@var{value} is shorthand for -global
The path to the image file in the local filesystem
@item aio
Specifies the AIO backend (threads/native, default: threads)
+@item locking
+Specifies whether the image file is protected with Linux OFD / POSIX locks. The
+default is to use the Linux Open File Descriptor API if available, otherwise no
+lock is applied. (auto/on/off, default: auto)
@end table
Example:
@example
@item key-delay-ms
Set keyboard delay, for key down and key up events, in milliseconds.
-Default is 1. Keyboards are low-bandwidth devices, so this slowdown
+Default is 10. Keyboards are low-bandwidth devices, so this slowdown
can help the device and guest to keep up and not lose events in case
events are arriving in bulk. Possible causes for the latter are flaky
network connections, or scripts for automated testing.
"-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
" use path to provide path to a character device; default is /dev/tpm0\n"
" use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
- " not provided it will be searched for in /sys/class/misc/tpm?/device\n",
+ " not provided it will be searched for in /sys/class/misc/tpm?/device\n"
+ "-tpmdev emulator,id=id,chardev=dev\n"
+ " configure the TPM device using chardev backend\n",
QEMU_ARCH_ALL)
STEXI
@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
@findex -tpmdev
-Backend type must be:
-@option{passthrough}.
+Backend type must be either one of the following:
+@option{passthrough}, @option{emulator}.
The specific backend type will determine the applicable options.
The @code{-tpmdev} option creates the TPM backend and requires a
Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
@code{tpmdev=tpm0} in the device option.
+@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
+
+(Linux-host only) Enable access to a TPM emulator using Unix domain socket based
+chardev backend.
+
+@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
+
+To create a TPM emulator backend device with chardev socket backend:
+@example
+
+-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
+
+@end example
+
@end table
ETEXI
ETEXI
DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
- "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
+ "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
+ " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
+ " Enable seccomp mode 2 system call filter (default 'off').\n" \
+ " use 'obsolete' to allow obsolete system calls that are provided\n" \
+ " by the kernel, but typically no longer used by modern\n" \
+ " C library implementations.\n" \
+ " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \
+ " its privileges by blacklisting all set*uid|gid system calls.\n" \
+ " The value 'children' will deny set*uid|gid system calls for\n" \
+ " main QEMU process but will allow forks and execves to run unprivileged\n" \
+ " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \
+ " blacklisting *fork and execve\n" \
+ " use 'resourcecontrol' to disable process affinity and schedular priority\n",
QEMU_ARCH_ALL)
STEXI
-@item -sandbox @var{arg}
+@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
@findex -sandbox
Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
disable it. The default is 'off'.
+@table @option
+@item obsolete=@var{string}
+Enable Obsolete system calls
+@item elevateprivileges=@var{string}
+Disable set*uid|gid system calls
+@item spawn=@var{string}
+Disable *fork and execve
+@item resourcecontrol=@var{string}
+Disable process affinity and schedular priority
+@end table
ETEXI
DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
command line and device configuration into file or dash @code{-}) character to print the
output to stdout. This can be later used as input file for @code{-readconfig} option.
ETEXI
-DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
- "-nodefconfig\n"
- " do not load default config files at startup\n",
- QEMU_ARCH_ALL)
-STEXI
-@item -nodefconfig
-@findex -nodefconfig
-Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
-The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
-ETEXI
+HXCOMM Deprecated, same as -no-user-config
+DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
"-no-user-config\n"
- " do not load user-provided config files at startup\n",
+ " do not load default user-provided config files at startup\n",
QEMU_ARCH_ALL)
STEXI
@item -no-user-config
@findex -no-user-config
The @code{-no-user-config} option makes QEMU not load any of the user-provided
-config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
-files from @var{datadir}.
+config files on @var{sysconfdir}.
ETEXI
DEF("trace", HAS_ARG, QEMU_OPTION_trace,
"-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
@table @option
-@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off}
+@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off},discard-data=@var{on|off}
Creates a memory file backend object, which can be used to back
the guest RAM with huge pages. The @option{id} parameter is a
The @option{share} boolean option determines whether the memory
region is marked as private to QEMU, or shared. The latter allows
a co-operating external process to access the QEMU memory region.
+Setting the @option{discard-data} boolean option to @var{on}
+indicates that file contents can be destroyed when QEMU exits,
+to avoid unnecessarily flushing data to the backing file. Note
+that @option{discard-data} is only an optimization, and QEMU
+might not discard file contents if it aborts unexpectedly or is
+terminated using SIGKILL.
@item -object rng-random,id=@var{id},filename=@var{/dev/random}
@option{tx}: the filter is attached to the transmit queue of the netdev,
where it will receive packets sent by the netdev.
-@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
+@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
-filter-mirror on netdev @var{netdevid},mirror net packet to chardev
-@var{chardevid}
+filter-mirror on netdev @var{netdevid},mirror net packet to chardev@var{chardevid}, if it has the vnet_hdr_support flag, filter-mirror will mirror packet with vnet_hdr_len.
-@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},
-outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
+@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
-@var{chardevid},and redirect indev's packet to filter.
+@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
+filter-redirector will redirect packet with vnet_hdr_len.
Create a filter-redirector we need to differ outdev id from indev id, id can not
be the same. we can just use indev or outdev, but at least one of indev or outdev
need to be specified.
-@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid}[,queue=@var{all|rx|tx}]
+@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
secondary from primary to keep secondary tcp connection,and rewrite
tcp packet to primary from secondary make tcp packet can be handled by
-client.
+client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
usage:
colo secondary:
The file format is libpcap, so it can be analyzed with tools such as tcpdump
or Wireshark.
-@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},
-outdev=@var{chardevid}
+@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
secondary packet. If the packets are same, we will output primary
packet to outdev@var{chardevid}, else we will notify colo-frame
do checkpoint and send primary packet to outdev@var{chardevid}.
+if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
we must use it with the help of filter-mirror and filter-redirector.
The simplest secure usage is to provide the secret via a file
- # echo -n "letmein" > mypasswd.txt
+ # printf "letmein" > mypasswd.txt
# $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
For greater security, AES-256-CBC should be used. To illustrate usage,
as raw bytes if desired.
@example
- # SECRET=$(echo -n "letmein" |
+ # SECRET=$(printf "letmein" |
openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
@end example
projects / mirror_qemu.git / blobdiff