The ordering semantics of +feature/-feature is tricky and not obvious, and it requires a custom option parser. Deprecate that syntax so we can eventually remove the custom -cpu option parser and plus_features/minus_features global variables in i386.
Signed-off-by: Eduardo Habkost <ehabk...@redhat.com> --- docs/system/deprecated.rst | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst index e20bfcb17a4..2c4b8d4b78b 100644 --- a/docs/system/deprecated.rst +++ b/docs/system/deprecated.rst @@ -127,6 +127,20 @@ Drives with interface types other than ``if=none`` are for onboard devices. It is possible to use drives the board doesn't pick up with -device. This usage is now deprecated. Use ``if=none`` instead. +``-cpu`` ``+feature`` and ``-feature`` syntax (since 6.0.0) +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' + +The ``-cpu ...,+feature`` and ``-cpu ...,-feature`` syntax for +enabling and disabling CPU features is deprecated. The ``-cpu +...,feature=on`` or ``-cpu ...,feature=off`` should be used +instead. + +Note that the ordering semantics of ``-cpu ...,-feature,+feature`` +is different from ``-cpu ...,feature=off,feature=on``. With the +former, the feature got disabled because ``-feature`` had +precedence, but with the latter the feature will be enabled +because options are applied in the order they appear. + QEMU Machine Protocol (QMP) commands ------------------------------------ -- 2.28.0
