From: Cédric Le Goater Date: Mon, 7 Nov 2022 16:13:49 +0000 (+0100) Subject: s390x/s390-virtio-ccw: Switch off zPCI enhancements on older machines X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=d3d1a406127f7da482eafbdc871c120c2770bb91;p=qemu.git s390x/s390-virtio-ccw: Switch off zPCI enhancements on older machines zPCI enhancement features (interpretation and forward assist) were recently introduced to improve performance on PCI passthrough devices. To maintain the same behaviour on older Z machines, deactivate the features with the associated properties. Signed-off-by: Cédric Le Goater Message-Id: <20221107161349.1032730-3-clg@kaod.org> Reviewed-by: Matthew Rosato Signed-off-by: Thomas Huth --- diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c index bb98d40792..7d80bc1837 100644 --- a/hw/s390x/s390-virtio-ccw.c +++ b/hw/s390x/s390-virtio-ccw.c @@ -844,9 +844,14 @@ static void ccw_machine_7_1_instance_options(MachineState *machine) static void ccw_machine_7_1_class_options(MachineClass *mc) { S390CcwMachineClass *s390mc = S390_CCW_MACHINE_CLASS(mc); + static GlobalProperty compat[] = { + { TYPE_S390_PCI_DEVICE, "interpret", "off", }, + { TYPE_S390_PCI_DEVICE, "forwarding-assist", "off", }, + }; ccw_machine_7_2_class_options(mc); compat_props_add(mc->compat_props, hw_compat_7_1, hw_compat_7_1_len); + compat_props_add(mc->compat_props, compat, G_N_ELEMENTS(compat)); s390mc->max_threads = S390_MAX_CPUS; } DEFINE_CCW_MACHINE(7_1, "7.1", false);