Commit 1de10b7d authored by Oliver Upton's avatar Oliver Upton
Browse files

KVM: arm64: Get rid of vCPU-scoped feature bitmap 

The vCPU-scoped feature bitmap was left in place a couple of releases
ago in case the change to VM-scoped vCPU features broke anyone. Nobody
has complained and the interop between VM and vCPU bitmaps is pretty
gross. Throw it out.

Link: https://lore.kernel.org/r/20230920195036.1169791-9-oliver.upton@linux.dev


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent 3d4b2a4c

arch/arm64/include/asm/kvm_emulate.h

+6 −7
Original line number Diff line number Diff line
@@ -54,6 +54,11 @@ void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu); 
int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2);

int kvm_inject_nested_irq(struct kvm_vcpu *vcpu);



static inline bool vcpu_has_feature(const struct kvm_vcpu *vcpu, int feature)

{

	return test_bit(feature, vcpu->kvm->arch.vcpu_features);

}



#if defined(__KVM_VHE_HYPERVISOR__) || defined(__KVM_NVHE_HYPERVISOR__)

static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)

{
@@ -62,7 +67,7 @@ static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu) 
#else

static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)

{

	return test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features);

	return vcpu_has_feature(vcpu, KVM_ARM_VCPU_EL1_32BIT);

}

#endif
@@ -565,12 +570,6 @@ static __always_inline void kvm_incr_pc(struct kvm_vcpu *vcpu) 
		vcpu_set_flag((v), e);					\

	} while (0)





static inline bool vcpu_has_feature(struct kvm_vcpu *vcpu, int feature)

{

	return test_bit(feature, vcpu->arch.features);

}



static __always_inline void kvm_write_cptr_el2(u64 val)

{

	if (has_vhe() || has_hvhe())

arch/arm64/include/asm/kvm_host.h

+0 −3
Original line number Diff line number Diff line
@@ -574,9 +574,6 @@ struct kvm_vcpu_arch { 
	/* Cache some mmu pages needed inside spinlock regions */

	struct kvm_mmu_memory_cache mmu_page_cache;



	/* feature flags */

	DECLARE_BITMAP(features, KVM_VCPU_MAX_FEATURES);



	/* Virtual SError ESR to restore when HCR_EL2.VSE is set */

	u64 vsesr_el2;

arch/arm64/include/asm/kvm_nested.h

+2 −1
Original line number Diff line number Diff line
@@ -2,13 +2,14 @@ 
#ifndef __ARM64_KVM_NESTED_H

#define __ARM64_KVM_NESTED_H



#include <asm/kvm_emulate.h>

#include <linux/kvm_host.h>



static inline bool vcpu_has_nv(const struct kvm_vcpu *vcpu)

{

	return (!__is_defined(__KVM_NVHE_HYPERVISOR__) &&

		cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) &&

		test_bit(KVM_ARM_VCPU_HAS_EL2, vcpu->arch.features));

		vcpu_has_feature(vcpu, KVM_ARM_VCPU_HAS_EL2));

}



extern bool __check_nv_sr_forward(struct kvm_vcpu *vcpu);

arch/arm64/kvm/arm.c

+4 −5
Original line number Diff line number Diff line
@@ -367,7 +367,6 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 


	/* Force users to call KVM_ARM_VCPU_INIT */

	vcpu_clear_flag(vcpu, VCPU_INITIALIZED);

	bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);



	vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
@@ -1263,7 +1262,8 @@ static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu, 
{

	unsigned long features = init->features[0];



	return !bitmap_equal(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES);

	return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features,

			     KVM_VCPU_MAX_FEATURES);

}



static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
@@ -1276,15 +1276,14 @@ static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 
	mutex_lock(&kvm->arch.config_lock);



	if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&

	    !bitmap_equal(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES))

	    kvm_vcpu_init_changed(vcpu, init))

		goto out_unlock;



	bitmap_copy(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES);

	bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);



	/* Now we know what it is, we can reset it. */

	kvm_reset_vcpu(vcpu);



	bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);

	set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);

	vcpu_set_flag(vcpu, VCPU_INITIALIZED);

	ret = 0;

arch/arm64/kvm/hypercalls.c

+1 −1
Original line number Diff line number Diff line
@@ -554,7 +554,7 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) 
	{

		bool wants_02;



		wants_02 = test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features);

		wants_02 = vcpu_has_feature(vcpu, KVM_ARM_VCPU_PSCI_0_2);



		switch (val) {

		case KVM_ARM_PSCI_0_1: