Commit 44bfe1f0 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: SVM: Make svm_x86_ops globally visible, clean up on-HyperV usage 

Make svm_x86_ops globally visible in anticipation of modifying the struct
in avic.c, and clean up the KVM-on-HyperV usage, as declaring _and using_
a local variable in a header that's only defined in one specific .c-file
is all kinds of ugly.

Opportunistically make svm_hv_enable_l2_tlb_flush() local to
svm_onhyperv.c, as the only reason it was visible was due to the
aforementioned shenanigans in svm_onhyperv.h.

Alternatively, svm_x86_ops could be explicitly passed to
svm_hv_hardware_setup() as a parameter.  While that approach is slightly
safer, e.g. avoids "hidden" updates, for better or worse, the Intel side
of KVM has already chosen to expose vt_x86_ops (and vt_init_ops).  Given
that svm_x86_ops is only truly consumed by kvm_ops_update, the odds of a
"hidden" update causing problems are extremely low.  So, absent a strong
reason to rework the VMX/TDX code, make svm_x86_ops visible, as having all
updates use exactly "svm_x86_ops." is advantageous in its own right.

No functional change intended.

Link: https://lore.kernel.org/r/20250919215934.1590410-2-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 29da8c82

arch/x86/kvm/svm/svm.c

+1 −1
Original line number Diff line number Diff line
@@ -5012,7 +5012,7 @@ static void *svm_alloc_apic_backing_page(struct kvm_vcpu *vcpu) 
	return page_address(page);

}



static struct kvm_x86_ops svm_x86_ops __initdata = {

struct kvm_x86_ops svm_x86_ops __initdata = {

	.name = KBUILD_MODNAME,



	.check_processor_compatibility = svm_check_processor_compat,

arch/x86/kvm/svm/svm.h

+2 −0
Original line number Diff line number Diff line
@@ -54,6 +54,8 @@ extern int lbrv; 


extern int tsc_aux_uret_slot __ro_after_init;



extern struct kvm_x86_ops svm_x86_ops __initdata;



/*

 * Clean bits in VMCB.

 * VMCB_ALL_CLEAN_MASK might also need to

arch/x86/kvm/svm/svm_onhyperv.c

+27 −1
Original line number Diff line number Diff line
@@ -15,7 +15,7 @@ 
#include "kvm_onhyperv.h"

#include "svm_onhyperv.h"



int svm_hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu)

static int svm_hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu)

{

	struct hv_vmcb_enlightenments *hve;

	hpa_t partition_assist_page = hv_get_partition_assist_page(vcpu);
@@ -35,3 +35,29 @@ int svm_hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu) 
	return 0;

}



__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.flush_remote_tlbs = hv_flush_remote_tlbs;

		svm_x86_ops.flush_remote_tlbs_range = hv_flush_remote_tlbs_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;

	}

}

arch/x86/kvm/svm/svm_onhyperv.h

+1 −30
Original line number Diff line number Diff line
@@ -13,9 +13,7 @@ 
#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);

__init void svm_hv_hardware_setup(void);



static inline bool svm_hv_is_enlightened_tlb_enabled(struct kvm_vcpu *vcpu)

{
@@ -40,33 +38,6 @@ static inline void svm_hv_init_vmcb(struct vmcb *vmcb) 
		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.flush_remote_tlbs = hv_flush_remote_tlbs;

		svm_x86_ops.flush_remote_tlbs_range = hv_flush_remote_tlbs_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)

{