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Revision 29694758

ID2969475869a6f33b8883c2fbf90252dcf617902e

Added by Eduardo Habkost over 11 years ago

pc: Reverse pc_init_pci() compatibility logic

Currently, the pc-1.4 machine init function enables PV EOI and then
calls the pc-1.2 machine init function. The problem with this approach
is that now we can't enable any additional compatibility code inside the
pc-1.2 init function because it would end up enabling the compatibility
behavior on pc-1.3 and pc-1.4 as well.

This reverses the logic so that the pc-1.2 machine init function will
disable PV EOI, and then call the pc-1.4 machine init function.

This way we can change older machine-types to enable compatibility
behavior, and the newer machine-types (pc-1.3, pc-q35-1.4 and
pc-i440fx-1.4) would just use the default behavior.

(This means that one nice side-effect of this change is that pc-q35-1.4
will get PV EOI enabled by default, too)

It would be interesting to eventually change pc_init_pci_no_kvmclock()
and pc_init_isa() to reuse pc_init_pci_1_2() as well (so we don't need
to duplicate compatibility code on those two functions). But this will
be probably much easier to do after we create a PCInitArgs struct for
the PC initialization arguments, and/or after we use global-properties
to implement the compatibility modes present in pc_init_pci_1_2().

Signed-off-by: Eduardo Habkost <>
Acked-by: Michael S. Tsirkin <>
Reviewed-by: Marcelo Tosatti <>
Signed-off-by: Andreas Färber <>

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