linux/arch/x86/kvm/svm/svm_onhyperv.h
Randy Dunlap 45dd9bc75d KVM: SVM: hyper-v: placate modpost section mismatch error
modpost reports section mismatch errors/warnings:
WARNING: modpost: vmlinux.o: section mismatch in reference: svm_hv_hardware_setup (section: .text) -> (unknown) (section: .init.data)
WARNING: modpost: vmlinux.o: section mismatch in reference: svm_hv_hardware_setup (section: .text) -> (unknown) (section: .init.data)
WARNING: modpost: vmlinux.o: section mismatch in reference: svm_hv_hardware_setup (section: .text) -> (unknown) (section: .init.data)

This "(unknown) (section: .init.data)" all refer to svm_x86_ops.

Tag svm_hv_hardware_setup() with __init to fix a modpost warning as the
non-stub implementation accesses __initdata (svm_x86_ops), i.e. would
generate a use-after-free if svm_hv_hardware_setup() were actually invoked
post-init.  The helper is only called from svm_hardware_setup(), which is
also __init, i.e. lack of __init is benign other than the modpost warning.

Fixes: 1e0c7d4075 ("KVM: SVM: hyper-v: Remote TLB flush for SVM")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Vineeth Pillai <viremana@linux.microsoft.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20230222073315.9081-1-rdunlap@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-02-22 13:32:07 -05:00

103 lines
2.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* KVM L1 hypervisor optimizations on Hyper-V for SVM.
*/
#ifndef __ARCH_X86_KVM_SVM_ONHYPERV_H__
#define __ARCH_X86_KVM_SVM_ONHYPERV_H__
#if IS_ENABLED(CONFIG_HYPERV)
#include "kvm_onhyperv.h"
#include "svm/hyperv.h"
static struct kvm_x86_ops svm_x86_ops;
int svm_hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu);
static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
{
struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;
BUILD_BUG_ON(sizeof(vmcb->control.hv_enlightenments) !=
sizeof(vmcb->control.reserved_sw));
if (npt_enabled &&
ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB)
hve->hv_enlightenments_control.enlightened_npt_tlb = 1;
if (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)
hve->hv_enlightenments_control.msr_bitmap = 1;
}
static inline __init void svm_hv_hardware_setup(void)
{
if (npt_enabled &&
ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB) {
pr_info(KBUILD_MODNAME ": Hyper-V enlightened NPT TLB flush enabled\n");
svm_x86_ops.tlb_remote_flush = hv_remote_flush_tlb;
svm_x86_ops.tlb_remote_flush_with_range =
hv_remote_flush_tlb_with_range;
}
if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH) {
int cpu;
pr_info(KBUILD_MODNAME ": Hyper-V Direct TLB Flush enabled\n");
for_each_online_cpu(cpu) {
struct hv_vp_assist_page *vp_ap =
hv_get_vp_assist_page(cpu);
if (!vp_ap)
continue;
vp_ap->nested_control.features.directhypercall = 1;
}
svm_x86_ops.enable_l2_tlb_flush =
svm_hv_enable_l2_tlb_flush;
}
}
static inline void svm_hv_vmcb_dirty_nested_enlightenments(
struct kvm_vcpu *vcpu)
{
struct vmcb *vmcb = to_svm(vcpu)->vmcb;
struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;
if (hve->hv_enlightenments_control.msr_bitmap)
vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
}
static inline void svm_hv_update_vp_id(struct vmcb *vmcb, struct kvm_vcpu *vcpu)
{
struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;
u32 vp_index = kvm_hv_get_vpindex(vcpu);
if (hve->hv_vp_id != vp_index) {
hve->hv_vp_id = vp_index;
vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
}
}
#else
static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
{
}
static inline __init void svm_hv_hardware_setup(void)
{
}
static inline void svm_hv_vmcb_dirty_nested_enlightenments(
struct kvm_vcpu *vcpu)
{
}
static inline void svm_hv_update_vp_id(struct vmcb *vmcb,
struct kvm_vcpu *vcpu)
{
}
#endif /* CONFIG_HYPERV */
#endif /* __ARCH_X86_KVM_SVM_ONHYPERV_H__ */