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| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2023-12-05 11:36:26 +0100 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2023-12-07 09:34:57 -0800 |
| commit | b4f69df0f65e97fec439130a0d0a8b9c7cc02df2 (patch) | |
| tree | 2d7e60178bfbd974c6a7eb361b0a1fb10918b60f /arch/x86/kvm/cpuid.c | |
| parent | f97314626734deaef49564a429c6f8eee3846bd3 (diff) | |
| download | linux-stable-b4f69df0f65e97fec439130a0d0a8b9c7cc02df2.tar.gz linux-stable-b4f69df0f65e97fec439130a0d0a8b9c7cc02df2.tar.bz2 linux-stable-b4f69df0f65e97fec439130a0d0a8b9c7cc02df2.zip | |
KVM: x86: Make Hyper-V emulation optional
Hyper-V emulation in KVM is a fairly big chunk and in some cases it may be
desirable to not compile it in to reduce module sizes as well as the attack
surface. Introduce CONFIG_KVM_HYPERV option to make it possible.
Note, there's room for further nVMX/nSVM code optimizations when
!CONFIG_KVM_HYPERV, this will be done in follow-up patches.
Reorganize Makefile a bit so all CONFIG_HYPERV and CONFIG_KVM_HYPERV files
are grouped together.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Tested-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Link: https://lore.kernel.org/r/20231205103630.1391318-13-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86/kvm/cpuid.c')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index dda6fc4cfae8..1b278a3f0689 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -314,11 +314,15 @@ EXPORT_SYMBOL_GPL(kvm_update_cpuid_runtime); static bool kvm_cpuid_has_hyperv(struct kvm_cpuid_entry2 *entries, int nent) { +#ifdef CONFIG_KVM_HYPERV struct kvm_cpuid_entry2 *entry; entry = cpuid_entry2_find(entries, nent, HYPERV_CPUID_INTERFACE, KVM_CPUID_INDEX_NOT_SIGNIFICANT); return entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX; +#else + return false; +#endif } static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) @@ -433,11 +437,13 @@ static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2, return 0; } +#ifdef CONFIG_KVM_HYPERV if (kvm_cpuid_has_hyperv(e2, nent)) { r = kvm_hv_vcpu_init(vcpu); if (r) return r; } +#endif r = kvm_check_cpuid(vcpu, e2, nent); if (r) |