qemu-deprecated.texi

   1 @node Deprecated features
   2 @appendix Deprecated features
   3
   4 In general features are intended to be supported indefinitely once
   5 introduced into QEMU. In the event that a feature needs to be removed,
   6 it will be listed in this appendix. The feature will remain functional
   7 for 2 releases prior to actual removal. Deprecated features may also
   8 generate warnings on the console when QEMU starts up, or if activated
   9 via a monitor command, however, this is not a mandatory requirement.
  10
  11 Prior to the 2.10.0 release there was no official policy on how
  12 long features would be deprecated prior to their removal, nor
  13 any documented list of which features were deprecated. Thus
  14 any features deprecated prior to 2.10.0 will be treated as if
  15 they were first deprecated in the 2.10.0 release.
  16
  17 What follows is a list of all features currently marked as
  18 deprecated.
  19
  20 @section System emulator command line arguments
  21
  22 @subsection -machine enforce-config-section=on|off (since 3.1)
  23
  24 The @option{enforce-config-section} parameter is replaced by the
  25 @option{-global migration.send-configuration=@var{on|off}} option.
  26
  27 @subsection -no-kvm (since 1.3.0)
  28
  29 The ``-no-kvm'' argument is now a synonym for setting
  30 ``-machine accel=tcg''.
  31
  32 @subsection -usbdevice (since 2.10.0)
  33
  34 The ``-usbdevice DEV'' argument is now a synonym for setting
  35 the ``-device usb-DEV'' argument instead. The deprecated syntax
  36 would automatically enable USB support on the machine type.
  37 If using the new syntax, USB support must be explicitly
  38 enabled via the ``-machine usb=on'' argument.
  39
  40 @subsection -no-frame (since 2.12.0)
  41
  42 The @code{--no-frame} argument works with SDL 1.2 only. The other user
  43 interfaces never implemented this in the first place. So this will be
  44 removed together with SDL 1.2 support.
  45
  46 @subsection -virtioconsole (since 3.0.0)
  47
  48 Option @option{-virtioconsole} has been replaced by
  49 @option{-device virtconsole}.
  50
  51 @subsection -clock (since 3.0.0)
  52
  53 The @code{-clock} option is ignored since QEMU version 1.7.0. There is no
  54 replacement since it is not needed anymore.
  55
  56 @subsection -enable-hax (since 3.0.0)
  57
  58 The @option{-enable-hax} option has been replaced by @option{-accel hax}.
  59 Both options have been introduced in QEMU version 2.9.0.
  60
  61 @subsection -drive file=json:@{...@{'driver':'file'@}@} (since 3.0)
  62
  63 The 'file' driver for drives is no longer appropriate for character or host
  64 devices and will only accept regular files (S_IFREG). The correct driver
  65 for these file types is 'host_cdrom' or 'host_device' as appropriate.
  66
  67 @subsection -net ...,name=@var{name} (since 3.1)
  68
  69 The @option{name} parameter of the @option{-net} option is a synonym
  70 for the @option{id} parameter, which should now be used instead.
  71
  72 @subsection -smp (invalid topologies) (since 3.1)
  73
  74 CPU topology properties should describe whole machine topology including
  75 possible CPUs.
  76
  77 However, historically it was possible to start QEMU with an incorrect topology
  78 where @math{@var{n} <= @var{sockets} * @var{cores} * @var{threads} < @var{maxcpus}},
  79 which could lead to an incorrect topology enumeration by the guest.
  80 Support for invalid topologies will be removed, the user must ensure
  81 topologies described with -smp include all possible cpus, i.e.
  82   @math{@var{sockets} * @var{cores} * @var{threads} = @var{maxcpus}}.
  83
  84 @section QEMU Machine Protocol (QMP) commands
  85
  86 @subsection block-dirty-bitmap-add "autoload" parameter (since 2.12.0)
  87
  88 "autoload" parameter is now ignored. All bitmaps are automatically loaded
  89 from qcow2 images.
  90
  91 @subsection query-cpus (since 2.12.0)
  92
  93 The ``query-cpus'' command is replaced by the ``query-cpus-fast'' command.
  94
  95 @subsection query-cpus-fast "arch" output member (since 3.0.0)
  96
  97 The ``arch'' output member of the ``query-cpus-fast'' command is
  98 replaced by the ``target'' output member.
  99
 100 @subsection cpu-add (since 4.0)
 101
 102 Use ``device_add'' for hotplugging vCPUs instead of ``cpu-add''.  See
 103 documentation of ``query-hotpluggable-cpus'' for additional
 104 details.
 105
 106 @section Human Monitor Protocol (HMP) commands
 107
 108 @subsection The hub_id parameter of 'hostfwd_add' / 'hostfwd_remove' (since 3.1)
 109
 110 The @option{[hub_id name]} parameter tuple of the 'hostfwd_add' and
 111 'hostfwd_remove' HMP commands has been replaced by @option{netdev_id}.
 112
 113 @subsection cpu-add (since 4.0)
 114
 115 Use ``device_add'' for hotplugging vCPUs instead of ``cpu-add''.  See
 116 documentation of ``query-hotpluggable-cpus'' for additional details.
 117
 118 @section System emulator devices
 119
 120 @subsection bluetooth (since 3.1)
 121
 122 The bluetooth subsystem is unmaintained since many years and likely bitrotten
 123 quite a bit. It will be removed without replacement unless some users speaks
 124 up at the @email{qemu-devel@@nongnu.org} mailing list with information about
 125 their usecases.
 126
 127 @section System emulator machines
 128
 129 @subsection pc-0.12, pc-0.13, pc-0.14 and pc-0.15 (since 4.0)
 130
 131 These machine types are very old and likely can not be used for live migration
 132 from old QEMU versions anymore. A newer machine type should be used instead.
 133
 134 @subsection prep (PowerPC) (since 3.1)
 135
 136 This machine type uses an unmaintained firmware, broken in lots of ways,
 137 and unable to start post-2004 operating systems. 40p machine type should be
 138 used instead.
 139
 140 @section Device options
 141
 142 @subsection Block device options
 143
 144 @subsubsection "backing": "" (since 2.12.0)
 145
 146 In order to prevent QEMU from automatically opening an image's backing
 147 chain, use ``"backing": null'' instead.
 148
 149 @subsubsection rbd keyvalue pair encoded filenames: "" (since 3.1.0)
 150
 151 Options for ``rbd'' should be specified according to its runtime options,
 152 like other block drivers.  Legacy parsing of keyvalue pair encoded
 153 filenames is useful to open images with the old format for backing files;
 154 These image files should be updated to use the current format.
 155
 156 Example of legacy encoding:
 157
 158 @code{json:@{"file.driver":"rbd", "file.filename":"rbd:rbd/name"@}}
 159
 160 The above, converted to the current supported format:
 161
 162 @code{json:@{"file.driver":"rbd", "file.pool":"rbd", "file.image":"name"@}}
 163
 164 @subsection vio-spapr-device device options
 165
 166 @subsubsection "irq": "" (since 3.0.0)
 167
 168 The ``irq'' property is obsoleted.