diff options
| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2021-09-02 11:35:25 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-10-01 19:04:45 +0200 |
| commit | 988f7b8bfeffbf521814d1e48c321f7674277512 (patch) | |
| tree | be12f2856161ae4b1463121f849245a5f8ceff57 /target | |
| parent | 8bdfec393a2ac67df9cecc0983d130db4a6bba58 (diff) | |
| download | qemu-988f7b8bfeffbf521814d1e48c321f7674277512.zip qemu-988f7b8bfeffbf521814d1e48c321f7674277512.tar.gz qemu-988f7b8bfeffbf521814d1e48c321f7674277512.tar.bz2 | |
i386: Support KVM_CAP_ENFORCE_PV_FEATURE_CPUID
By default, KVM allows the guest to use all currently supported PV features
even when they were not announced in guest visible CPUIDs. Introduce a new
"kvm-pv-enforce-cpuid" flag to limit the supported feature set to the
exposed features. The feature is supported by Linux >= 5.10 and is not
enabled by default in QEMU.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210902093530.345756-4-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'target')
| -rw-r--r-- | target/i386/cpu.c | 2 | ||||
| -rw-r--r-- | target/i386/cpu.h | 3 | ||||
| -rw-r--r-- | target/i386/kvm/kvm.c | 10 |
3 files changed, 15 insertions, 0 deletions
diff --git a/target/i386/cpu.c b/target/i386/cpu.c index cacec60..598019d 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -6860,6 +6860,8 @@ static Property x86_cpu_properties[] = { DEFINE_PROP_BOOL("l3-cache", X86CPU, enable_l3_cache, true), DEFINE_PROP_BOOL("kvm-no-smi-migration", X86CPU, kvm_no_smi_migration, false), + DEFINE_PROP_BOOL("kvm-pv-enforce-cpuid", X86CPU, kvm_pv_enforce_cpuid, + false), DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true), DEFINE_PROP_BOOL("tcg-cpuid", X86CPU, expose_tcg, true), DEFINE_PROP_BOOL("x-migrate-smi-count", X86CPU, migrate_smi_count, diff --git a/target/i386/cpu.h b/target/i386/cpu.h index 29552dc..c990150 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -1802,6 +1802,9 @@ struct X86CPU { /* Stop SMI delivery for migration compatibility with old machines */ bool kvm_no_smi_migration; + /* Forcefully disable KVM PV features not exposed in guest CPUIDs */ + bool kvm_pv_enforce_cpuid; + /* Number of physical address bits supported */ uint32_t phys_bits; diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index 7f1b060..d6a70c2 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -1629,6 +1629,16 @@ int kvm_arch_init_vcpu(CPUState *cs) cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused); + if (cpu->kvm_pv_enforce_cpuid) { + r = kvm_vcpu_enable_cap(cs, KVM_CAP_ENFORCE_PV_FEATURE_CPUID, 0, 1); + if (r < 0) { + fprintf(stderr, + "failed to enable KVM_CAP_ENFORCE_PV_FEATURE_CPUID: %s", + strerror(-r)); + abort(); + } + } + for (i = 0; i <= limit; i++) { if (cpuid_i == KVM_MAX_CPUID_ENTRIES) { fprintf(stderr, "unsupported level value: 0x%x\n", limit); |