lkml.org 
[lkml]   [2022]   [Oct]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH v2 6/8] KVM: x86: compile out vendor-specific code if SMM is disabled
    From
    Date
    On Thu, 2022-09-29 at 13:20 -0400, Paolo Bonzini wrote:
    > Vendor-specific code that deals with SMI injection and saving/restoring
    > SMM state is not needed if CONFIG_KVM_SMM is disabled, so remove the
    > four callbacks smi_allowed, enter_smm, leave_smm and enable_smi_window.
    > The users in svm/nested.c and x86.c also have to be compiled out; the
    > amount of #ifdef'ed code is small and it's not worth moving it to
    > smm.c.
    >
    > enter_smm is now used only within #ifdef CONFIG_KVM_SMM, and the stub
    > can therefore be removed.
    >
    > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
    > ---
    > arch/x86/include/asm/kvm-x86-ops.h | 2 ++
    > arch/x86/include/asm/kvm_host.h | 2 ++
    > arch/x86/kvm/smm.h | 1 -
    > arch/x86/kvm/svm/nested.c | 2 ++
    > arch/x86/kvm/svm/svm.c | 4 ++++
    > arch/x86/kvm/vmx/vmx.c | 4 ++++
    > arch/x86/kvm/x86.c | 4 ++++
    > 7 files changed, 18 insertions(+), 1 deletion(-)
    >
    > diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
    > index 82ba4a564e58..ea58e67e9a67 100644
    > --- a/arch/x86/include/asm/kvm-x86-ops.h
    > +++ b/arch/x86/include/asm/kvm-x86-ops.h
    > @@ -110,10 +110,12 @@ KVM_X86_OP_OPTIONAL_RET0(dy_apicv_has_pending_interrupt)
    > KVM_X86_OP_OPTIONAL(set_hv_timer)
    > KVM_X86_OP_OPTIONAL(cancel_hv_timer)
    > KVM_X86_OP(setup_mce)
    > +#ifdef CONFIG_KVM_SMM
    > KVM_X86_OP(smi_allowed)
    > KVM_X86_OP(enter_smm)
    > KVM_X86_OP(leave_smm)
    > KVM_X86_OP(enable_smi_window)
    > +#endif
    > KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
    > KVM_X86_OP_OPTIONAL(mem_enc_register_region)
    > KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
    > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
    > index b7d078cd768d..cb88da02d965 100644
    > --- a/arch/x86/include/asm/kvm_host.h
    > +++ b/arch/x86/include/asm/kvm_host.h
    > @@ -1606,10 +1606,12 @@ struct kvm_x86_ops {
    >
    > void (*setup_mce)(struct kvm_vcpu *vcpu);
    >
    > +#ifdef CONFIG_KVM_SMM
    > int (*smi_allowed)(struct kvm_vcpu *vcpu, bool for_injection);
    > int (*enter_smm)(struct kvm_vcpu *vcpu, char *smstate);
    > int (*leave_smm)(struct kvm_vcpu *vcpu, const char *smstate);
    > void (*enable_smi_window)(struct kvm_vcpu *vcpu);
    > +#endif
    >
    > int (*mem_enc_ioctl)(struct kvm *kvm, void __user *argp);
    > int (*mem_enc_register_region)(struct kvm *kvm, struct kvm_enc_region *argp);
    > diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
    > index 4c699fee4492..7ccce6b655ca 100644
    > --- a/arch/x86/kvm/smm.h
    > +++ b/arch/x86/kvm/smm.h
    > @@ -28,7 +28,6 @@ void process_smi(struct kvm_vcpu *vcpu);
    > static inline int kvm_inject_smi(struct kvm_vcpu *vcpu) { return -ENOTTY; }
    > static inline bool is_smm(struct kvm_vcpu *vcpu) { return false; }
    > static inline void kvm_smm_changed(struct kvm_vcpu *vcpu, bool in_smm) { WARN_ON_ONCE(1); }
    > -static inline void enter_smm(struct kvm_vcpu *vcpu) { WARN_ON_ONCE(1); }
    > static inline void process_smi(struct kvm_vcpu *vcpu) { WARN_ON_ONCE(1); }
    >
    > /*
    > diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
    > index cc0fd75f7cba..b258d6988f5d 100644
    > --- a/arch/x86/kvm/svm/nested.c
    > +++ b/arch/x86/kvm/svm/nested.c
    > @@ -1378,6 +1378,7 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu)
    > return 0;
    > }
    >
    > +#ifdef CONFIG_KVM_SMM
    > if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
    > if (block_nested_events)
    > return -EBUSY;
    > @@ -1386,6 +1387,7 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu)
    > nested_svm_simple_vmexit(svm, SVM_EXIT_SMI);
    > return 0;
    > }
    > +#endif
    >
    > if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
    > if (block_nested_events)
    > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
    > index 6f7ceb35d2ff..2200b8aa7273 100644
    > --- a/arch/x86/kvm/svm/svm.c
    > +++ b/arch/x86/kvm/svm/svm.c
    > @@ -4408,6 +4408,7 @@ static void svm_setup_mce(struct kvm_vcpu *vcpu)
    > vcpu->arch.mcg_cap &= 0x1ff;
    > }
    >
    > +#ifdef CONFIG_KVM_SMM
    > bool svm_smi_blocked(struct kvm_vcpu *vcpu)
    > {
    > struct vcpu_svm *svm = to_svm(vcpu);
    > @@ -4557,6 +4558,7 @@ static void svm_enable_smi_window(struct kvm_vcpu *vcpu)
    > /* We must be in SMM; RSM will cause a vmexit anyway. */
    > }
    > }
    > +#endif
    >
    > static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
    > void *insn, int insn_len)
    > @@ -4832,10 +4834,12 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
    > .pi_update_irte = avic_pi_update_irte,
    > .setup_mce = svm_setup_mce,
    >
    > +#ifdef CONFIG_KVM_SMM
    > .smi_allowed = svm_smi_allowed,
    > .enter_smm = svm_enter_smm,
    > .leave_smm = svm_leave_smm,
    > .enable_smi_window = svm_enable_smi_window,
    > +#endif
    >
    > .mem_enc_ioctl = sev_mem_enc_ioctl,
    > .mem_enc_register_region = sev_mem_enc_register_region,
    > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
    > index b22330a15adb..107fc035c91b 100644
    > --- a/arch/x86/kvm/vmx/vmx.c
    > +++ b/arch/x86/kvm/vmx/vmx.c
    > @@ -7905,6 +7905,7 @@ static void vmx_setup_mce(struct kvm_vcpu *vcpu)
    > ~FEAT_CTL_LMCE_ENABLED;
    > }
    >
    > +#ifdef CONFIG_KVM_SMM
    > static int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
    > {
    > /* we need a nested vmexit to enter SMM, postpone if run is pending */
    > @@ -7959,6 +7960,7 @@ static void vmx_enable_smi_window(struct kvm_vcpu *vcpu)
    > {
    > /* RSM will cause a vmexit anyway. */
    > }
    > +#endif
    >
    > static bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
    > {
    > @@ -8126,10 +8128,12 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
    >
    > .setup_mce = vmx_setup_mce,
    >
    > +#ifdef CONFIG_KVM_SMM
    > .smi_allowed = vmx_smi_allowed,
    > .enter_smm = vmx_enter_smm,
    > .leave_smm = vmx_leave_smm,
    > .enable_smi_window = vmx_enable_smi_window,
    > +#endif
    >
    > .can_emulate_instruction = vmx_can_emulate_instruction,
    > .apic_init_signal_blocked = vmx_apic_init_signal_blocked,
    > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
    > index a9e050aefea6..e22184bad92b 100644
    > --- a/arch/x86/kvm/x86.c
    > +++ b/arch/x86/kvm/x86.c
    > @@ -9863,6 +9863,7 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
    > * in order to make progress and get back here for another iteration.
    > * The kvm_x86_ops hooks communicate this by returning -EBUSY.
    > */
    > +#ifdef CONFIG_KVM_SMM
    > if (vcpu->arch.smi_pending) {
    > r = can_inject ? static_call(kvm_x86_smi_allowed)(vcpu, true) : -EBUSY;
    > if (r < 0)
    > @@ -9875,6 +9876,7 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
    > } else
    > static_call(kvm_x86_enable_smi_window)(vcpu);
    > }
    > +#endif
    >
    > if (vcpu->arch.nmi_pending) {
    > r = can_inject ? static_call(kvm_x86_nmi_allowed)(vcpu, true) : -EBUSY;
    > @@ -12491,10 +12493,12 @@ static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu)
    > static_call(kvm_x86_nmi_allowed)(vcpu, false)))
    > return true;
    >
    > +#ifdef CONFIG_KVM_SMM
    > if (kvm_test_request(KVM_REQ_SMI, vcpu) ||
    > (vcpu->arch.smi_pending &&
    > static_call(kvm_x86_smi_allowed)(vcpu, false)))
    > return true;
    > +#endif
    >
    > if (kvm_arch_interrupt_allowed(vcpu) &&
    > (kvm_cpu_has_interrupt(vcpu) ||


    Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>

    Best regards,
    Maxim Levitsky


    \
     
     \ /
      Last update: 2022-10-24 21:26    [W:3.936 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site