From 87562052c965ba7de6dc490434e53691fe46c898 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Tue, 5 Dec 2023 11:36:15 +0100 Subject: [PATCH] KVM: x86/xen: Remove unneeded xen context from kvm_arch when !CONFIG_KVM_XEN Saving a few bytes of memory per KVM VM is certainly great but what's more important is the ability to see where the code accesses Xen emulation context while CONFIG_KVM_XEN is not enabled. Currently, kvm_cpu_get_extint() is the only such place and it is harmless: kvm_xen_has_interrupt() always returns '0' when !CONFIG_KVM_XEN. No functional change intended. Reviewed-by: Maxim Levitsky Tested-by: Jeremi Piotrowski Signed-off-by: Vitaly Kuznetsov Link: https://lore.kernel.org/r/20231205103630.1391318-2-vkuznets@redhat.com Signed-off-by: Sean Christopherson --- arch/x86/include/asm/kvm_host.h | 5 +++++ arch/x86/kvm/irq.c | 2 ++ 2 files changed, 7 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 5e5e9e0abd4a..b0ca65632f2c 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1136,6 +1136,7 @@ struct msr_bitmap_range { unsigned long *bitmap; }; +#ifdef CONFIG_KVM_XEN /* Xen emulation context */ struct kvm_xen { struct mutex xen_lock; @@ -1147,6 +1148,7 @@ struct kvm_xen { struct idr evtchn_ports; unsigned long poll_mask[BITS_TO_LONGS(KVM_MAX_VCPUS)]; }; +#endif enum kvm_irqchip_mode { KVM_IRQCHIP_NONE, @@ -1349,7 +1351,10 @@ struct kvm_arch { struct hlist_head mask_notifier_list; struct kvm_hv hyperv; + +#ifdef CONFIG_KVM_XEN struct kvm_xen xen; +#endif bool backwards_tsc_observed; bool boot_vcpu_runs_old_kvmclock; diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c index b2c397dd2bc6..ad9ca8a60144 100644 --- a/arch/x86/kvm/irq.c +++ b/arch/x86/kvm/irq.c @@ -118,8 +118,10 @@ static int kvm_cpu_get_extint(struct kvm_vcpu *v) if (!lapic_in_kernel(v)) return v->arch.interrupt.nr; +#ifdef CONFIG_KVM_XEN if (kvm_xen_has_interrupt(v)) return v->kvm->arch.xen.upcall_vector; +#endif if (irqchip_split(v->kvm)) { int vector = v->arch.pending_external_vector; -- 2.49.0