From 027ac0cb516cca4ce8a88dcca2f759c77e0e374b Mon Sep 17 00:00:00 2001 From: Vladislav Yaroshchuk Date: Wed, 13 Jan 2021 23:53:23 +0300 Subject: [PATCH] target/i386/hvf: add rdmsr 35H MSR_CORE_THREAD_COUNT Some guests (ex. Darwin-XNU) can attemp to read this MSR to retrieve and validate CPU topology comparing it to ACPI MADT content MSR description from Intel Manual: 35H: MSR_CORE_THREAD_COUNT: Configured State of Enabled Processor Core Count and Logical Processor Count Bits 15:0 THREAD_COUNT The number of logical processors that are currently enabled in the physical package Bits 31:16 Core_COUNT The number of processor cores that are currently enabled in the physical package Bits 63:32 Reserved Signed-off-by: Vladislav Yaroshchuk Message-Id: <20210113205323.33310-1-yaroshchuk2000@gmail.com> [RB: reordered MSR definition and dropped u suffix from shift offset] Signed-off-by: Roman Bolshakov Signed-off-by: Paolo Bonzini --- target/i386/cpu.h | 1 + target/i386/hvf/x86_emu.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/target/i386/cpu.h b/target/i386/cpu.h index 8d599bb5b8..82c1ac00ef 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -368,6 +368,7 @@ typedef enum X86Seg { #define MSR_IA32_SMBASE 0x9e #define MSR_SMI_COUNT 0x34 +#define MSR_CORE_THREAD_COUNT 0x35 #define MSR_MTRRcap 0xfe #define MSR_MTRRcap_VCNT 8 #define MSR_MTRRcap_FIXRANGE_SUPPORT (1 << 8) diff --git a/target/i386/hvf/x86_emu.c b/target/i386/hvf/x86_emu.c index da570e352b..e52c39ddb1 100644 --- a/target/i386/hvf/x86_emu.c +++ b/target/i386/hvf/x86_emu.c @@ -668,6 +668,7 @@ void simulate_rdmsr(struct CPUState *cpu) { X86CPU *x86_cpu = X86_CPU(cpu); CPUX86State *env = &x86_cpu->env; + CPUState *cs = env_cpu(env); uint32_t msr = ECX(env); uint64_t val = 0; @@ -745,6 +746,10 @@ void simulate_rdmsr(struct CPUState *cpu) case MSR_MTRRdefType: val = env->mtrr_deftype; break; + case MSR_CORE_THREAD_COUNT: + val = cs->nr_threads * cs->nr_cores; /* thread count, bits 15..0 */ + val |= ((uint32_t)cs->nr_cores << 16); /* core count, bits 31..16 */ + break; default: /* fprintf(stderr, "%s: unknown msr 0x%x\n", __func__, msr); */ val = 0;