From d72e41f9a16360eb23e9d943fa7e33291c5fcd87 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 17 Feb 2020 16:23:18 -0500 Subject: [PATCH 03/12] target/i386: kvm: initialize feature MSRs very early MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Paolo Bonzini Message-id: <20200217162323.2572-2-pbonzini@redhat.com> Patchwork-id: 93896 O-Subject: [RHEL7.9 qemu-kvm-rhev PATCH 1/6] target/i386: kvm: initialize feature MSRs very early Bugzilla: 1791653 RH-Acked-by: Maxim Levitsky RH-Acked-by: Philippe Mathieu-Daudé RH-Acked-by: Dr. David Alan Gilbert Some read-only MSRs affect the behavior of ioctls such as KVM_SET_NESTED_STATE. We can initialize them once and for all right after the CPU is realized, since they will never be modified by the guest. Reported-by: Qingua Cheng Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini Message-Id: <1579544504-3616-2-git-send-email-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini (cherry picked from commit 420ae1fc51c99abfd03b1c590f55617edd2a2bed) [RHEL7: no MSR_IA32_CORE_CAPABILITY] Signed-off-by: Jon Maloy --- target/i386/kvm.c | 55 +++++++++++++++++++++++++++--------------- target/i386/kvm_i386.h | 1 + 2 files changed, 36 insertions(+), 20 deletions(-) diff --git a/target/i386/kvm.c b/target/i386/kvm.c index a6e5a87cf5..d8a4dbfde3 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -65,6 +65,8 @@ * 255 kvm_msr_entry structs */ #define MSR_BUF_SIZE 4096 +static void kvm_init_msrs(X86CPU *cpu); + const KVMCapabilityInfo kvm_arch_required_capabilities[] = { KVM_CAP_INFO(SET_TSS_ADDR), KVM_CAP_INFO(EXT_CPUID), @@ -1175,6 +1177,8 @@ int kvm_arch_init_vcpu(CPUState *cs) has_msr_tsc_aux = false; } + kvm_init_msrs(cpu); + return 0; fail: @@ -1797,11 +1801,40 @@ static int kvm_put_msr_feature_control(X86CPU *cpu) return 0; } +static int kvm_buf_set_msrs(X86CPU *cpu) +{ + int ret = kvm_vcpu_ioctl(CPU(cpu), KVM_SET_MSRS, cpu->kvm_msr_buf); + if (ret < 0) { + return ret; + } + + if (ret < cpu->kvm_msr_buf->nmsrs) { + struct kvm_msr_entry *e = &cpu->kvm_msr_buf->entries[ret]; + error_report("error: failed to set MSR 0x%" PRIx32 " to 0x%" PRIx64, + (uint32_t)e->index, (uint64_t)e->data); + } + + assert(ret == cpu->kvm_msr_buf->nmsrs); + return 0; +} + +static void kvm_init_msrs(X86CPU *cpu) +{ + CPUX86State *env = &cpu->env; + + kvm_msr_buf_reset(cpu); + if (has_msr_arch_capabs) { + kvm_msr_entry_add(cpu, MSR_IA32_ARCH_CAPABILITIES, + env->features[FEAT_ARCH_CAPABILITIES]); + } + + assert(kvm_buf_set_msrs(cpu) == 0); +} + static int kvm_put_msrs(X86CPU *cpu, int level) { CPUX86State *env = &cpu->env; int i; - int ret; kvm_msr_buf_reset(cpu); @@ -1856,12 +1889,6 @@ static int kvm_put_msrs(X86CPU *cpu, int level) } #endif - /* If host supports feature MSR, write down. */ - if (has_msr_arch_capabs) { - kvm_msr_entry_add(cpu, MSR_IA32_ARCH_CAPABILITIES, - env->features[FEAT_ARCH_CAPABILITIES]); - } - /* * The following MSRs have side effects on the guest or are too heavy * for normal writeback. Limit them to reset or full state updates. @@ -2040,19 +2067,7 @@ static int kvm_put_msrs(X86CPU *cpu, int level) } } - ret = kvm_vcpu_ioctl(CPU(cpu), KVM_SET_MSRS, cpu->kvm_msr_buf); - if (ret < 0) { - return ret; - } - - if (ret < cpu->kvm_msr_buf->nmsrs) { - struct kvm_msr_entry *e = &cpu->kvm_msr_buf->entries[ret]; - error_report("error: failed to set MSR 0x%" PRIx32 " to 0x%" PRIx64, - (uint32_t)e->index, (uint64_t)e->data); - } - - assert(ret == cpu->kvm_msr_buf->nmsrs); - return 0; + return kvm_buf_set_msrs(cpu); } diff --git a/target/i386/kvm_i386.h b/target/i386/kvm_i386.h index 1de9876cd9..856044750e 100644 --- a/target/i386/kvm_i386.h +++ b/target/i386/kvm_i386.h @@ -69,4 +69,5 @@ void kvm_put_apicbase(X86CPU *cpu, uint64_t value); bool kvm_enable_x2apic(void); bool kvm_has_x2apic_api(void); + #endif -- 2.18.2