From 00dc02d284eab0890936ec47c0b7baba5e3b4e37 Mon Sep 17 00:00:00 2001 From: Igor Mammedov Date: Wed, 23 Sep 2020 05:46:40 -0400 Subject: x86: lpc9: let firmware negotiate 'CPU hotplug with SMI' features It will allow firmware to notify QEMU that firmware requires SMI being triggered on CPU hot[un]plug, so that it would be able to account for hotplugged CPU and relocate it to new SMM base and/or safely remove CPU on unplug. Using negotiated features, follow up patches will insert SMI upcall into AML code, to make sure that firmware processes hotplug before guest OS would attempt to use new CPU. Signed-off-by: Igor Mammedov Reviewed-by: Laszlo Ersek Tested-by: Laszlo Ersek Message-Id: <20200923094650.1301166-2-imammedo@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/pc.c | 4 +++- hw/isa/lpc_ich9.c | 13 +++++++++++++ include/hw/i386/ich9.h | 2 ++ 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 50e8317..2c6194e 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -97,7 +97,9 @@ #include "trace.h" #include CONFIG_DEVICES -GlobalProperty pc_compat_5_1[] = {}; +GlobalProperty pc_compat_5_1[] = { + { "ICH9-LPC", "x-smi-cpu-hotplug", "off" }, +}; const size_t pc_compat_5_1_len = G_N_ELEMENTS(pc_compat_5_1); GlobalProperty pc_compat_5_0[] = { diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c index 3303d2e..a54b3ec 100644 --- a/hw/isa/lpc_ich9.c +++ b/hw/isa/lpc_ich9.c @@ -373,6 +373,15 @@ static void smi_features_ok_callback(void *opaque) /* guest requests invalid features, leave @features_ok at zero */ return; } + if (!(guest_features & BIT_ULL(ICH9_LPC_SMI_F_BROADCAST_BIT)) && + guest_features & (BIT_ULL(ICH9_LPC_SMI_F_CPU_HOTPLUG_BIT) | + BIT_ULL(ICH9_LPC_SMI_F_CPU_HOT_UNPLUG_BIT))) { + /* + * cpu hot-[un]plug with SMI requires SMI broadcast, + * leave @features_ok at zero + */ + return; + } /* valid feature subset requested, lock it down, report success */ lpc->smi_negotiated_features = guest_features; @@ -747,6 +756,10 @@ static Property ich9_lpc_properties[] = { DEFINE_PROP_BOOL("noreboot", ICH9LPCState, pin_strap.spkr_hi, true), DEFINE_PROP_BIT64("x-smi-broadcast", ICH9LPCState, smi_host_features, ICH9_LPC_SMI_F_BROADCAST_BIT, true), + DEFINE_PROP_BIT64("x-smi-cpu-hotplug", ICH9LPCState, smi_host_features, + ICH9_LPC_SMI_F_CPU_HOTPLUG_BIT, true), + DEFINE_PROP_BIT64("x-smi-cpu-hotunplug", ICH9LPCState, smi_host_features, + ICH9_LPC_SMI_F_CPU_HOT_UNPLUG_BIT, false), DEFINE_PROP_END_OF_LIST(), }; diff --git a/include/hw/i386/ich9.h b/include/hw/i386/ich9.h index 48b442b..703d560 100644 --- a/include/hw/i386/ich9.h +++ b/include/hw/i386/ich9.h @@ -247,5 +247,7 @@ struct ICH9LPCState { /* bit positions used in fw_cfg SMI feature negotiation */ #define ICH9_LPC_SMI_F_BROADCAST_BIT 0 +#define ICH9_LPC_SMI_F_CPU_HOTPLUG_BIT 1 +#define ICH9_LPC_SMI_F_CPU_HOT_UNPLUG_BIT 2 #endif /* HW_ICH9_H */ -- cgit v1.1