From 217f1b4a72153cf8d556e9d45919e9222c38d25e Mon Sep 17 00:00:00 2001 From: Haozhong Zhang Date: Thu, 23 Jun 2016 14:15:43 +0800 Subject: [PATCH] target-i386: Publish advised value of MSR_IA32_FEATURE_CONTROL via fw_cfg It's a prerequisite that certain bits of MSR_IA32_FEATURE_CONTROL should be set before some features (e.g. VMX and LMCE) can be used, which is usually done by the firmware. This patch adds a fw_cfg file "etc/msr_feature_control" which contains the advised value of MSR_IA32_FEATURE_CONTROL and can be used by guest firmware (e.g. SeaBIOS). Suggested-by: Paolo Bonzini Signed-off-by: Haozhong Zhang Reviewed-by: Paolo Bonzini Signed-off-by: Eduardo Habkost --- hw/i386/pc.c | 29 +++++++++++++++++++++++++++++ target-i386/cpu.h | 4 ++++ 2 files changed, 33 insertions(+) diff --git a/hw/i386/pc.c b/hw/i386/pc.c index d0df3c1013..f56e225a99 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -1166,6 +1166,34 @@ void pc_cpus_init(PCMachineState *pcms) smbios_set_cpuid(cpu->env.cpuid_version, cpu->env.features[FEAT_1_EDX]); } +static void pc_build_feature_control_file(PCMachineState *pcms) +{ + X86CPU *cpu = X86_CPU(pcms->possible_cpus->cpus[0].cpu); + CPUX86State *env = &cpu->env; + uint32_t unused, ecx, edx; + uint64_t feature_control_bits = 0; + uint64_t *val; + + cpu_x86_cpuid(env, 1, 0, &unused, &unused, &ecx, &edx); + if (ecx & CPUID_EXT_VMX) { + feature_control_bits |= FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX; + } + + if ((edx & (CPUID_EXT2_MCE | CPUID_EXT2_MCA)) == + (CPUID_EXT2_MCE | CPUID_EXT2_MCA) && + (env->mcg_cap & MCG_LMCE_P)) { + feature_control_bits |= FEATURE_CONTROL_LMCE; + } + + if (!feature_control_bits) { + return; + } + + val = g_malloc(sizeof(*val)); + *val = cpu_to_le64(feature_control_bits | FEATURE_CONTROL_LOCKED); + fw_cfg_add_file(pcms->fw_cfg, "etc/msr_feature_control", val, sizeof(*val)); +} + static void pc_machine_done(Notifier *notifier, void *data) { @@ -1193,6 +1221,7 @@ void pc_machine_done(Notifier *notifier, void *data) acpi_setup(); if (pcms->fw_cfg) { pc_build_smbios(pcms->fw_cfg); + pc_build_feature_control_file(pcms); } } diff --git a/target-i386/cpu.h b/target-i386/cpu.h index 54c3fd6561..5c7a2791f3 100644 --- a/target-i386/cpu.h +++ b/target-i386/cpu.h @@ -332,6 +332,10 @@ #define MSR_TSC_ADJUST 0x0000003b #define MSR_IA32_TSCDEADLINE 0x6e0 +#define FEATURE_CONTROL_LOCKED (1<<0) +#define FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX (1<<2) +#define FEATURE_CONTROL_LMCE (1<<20) + #define MSR_P6_PERFCTR0 0xc1 #define MSR_IA32_SMBASE 0x9e -- 2.11.0