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Commit 3f5c90b8 authored by Christoffer Dall's avatar Christoffer Dall Committed by Marc Zyngier
Browse files

KVM: arm64: Introduce VHE-specific kvm_vcpu_run 



So far this is mostly (see below) a copy of the legacy non-VHE switch
function, but we will start reworking these functions in separate
directions to work on VHE and non-VHE in the most optimal way in later
patches.

The only difference after this patch between the VHE and non-VHE run
functions is that we omit the branch-predictor variant-2 hardening for
QC Falkor CPUs, because this workaround is specific to a series of
non-VHE ARMv8.0 CPUs.

Reviewed-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
parent dc251406

arch/arm/include/asm/kvm_asm.h

+4 −1
Original line number Diff line number Diff line
@@ -70,7 +70,10 @@ extern void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu); 


extern void __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high);



extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);

/* no VHE on 32-bit :( */

static inline int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) { BUG(); return 0; }



extern int __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu);



extern void __init_stage2_translation(void);

arch/arm/kvm/hyp/switch.c

+1 −1
Original line number Diff line number Diff line
@@ -154,7 +154,7 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu) 
	return true;

}



int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)

int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)

{

	struct kvm_cpu_context *host_ctxt;

	struct kvm_cpu_context *guest_ctxt;

arch/arm64/include/asm/kvm_asm.h

+3 −1
Original line number Diff line number Diff line
@@ -58,7 +58,9 @@ extern void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu); 


extern void __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high);



extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);

extern int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu);



extern int __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu);



extern u64 __vgic_v3_get_ich_vtr_el2(void);

extern u64 __vgic_v3_read_vmcr(void);

arch/arm64/include/asm/kvm_host.h

+7 −0
Original line number Diff line number Diff line
@@ -428,6 +428,13 @@ static inline void kvm_arm_vhe_guest_enter(void) 
static inline void kvm_arm_vhe_guest_exit(void)

{

	local_daif_restore(DAIF_PROCCTX_NOIRQ);



	/*

	 * When we exit from the guest we change a number of CPU configuration

	 * parameters, such as traps.  Make sure these changes take effect

	 * before running the host or additional guests.

	 */

	isb();

}



static inline bool kvm_arm_harden_branch_predictor(void)

arch/arm64/kvm/hyp/switch.c

+65 −1
Original line number Diff line number Diff line
@@ -362,7 +362,71 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code) 
	return false;

}



int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)

/* Switch to the guest for VHE systems running in EL2 */

int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)

{

	struct kvm_cpu_context *host_ctxt;

	struct kvm_cpu_context *guest_ctxt;

	bool fp_enabled;

	u64 exit_code;



	vcpu = kern_hyp_va(vcpu);



	host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);

	host_ctxt->__hyp_running_vcpu = vcpu;

	guest_ctxt = &vcpu->arch.ctxt;



	__sysreg_save_host_state(host_ctxt);



	__activate_traps(vcpu);

	__activate_vm(vcpu);



	__vgic_restore_state(vcpu);

	__timer_enable_traps(vcpu);



	/*

	 * We must restore the 32-bit state before the sysregs, thanks

	 * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72).

	 */

	__sysreg32_restore_state(vcpu);

	__sysreg_restore_guest_state(guest_ctxt);

	__debug_switch_to_guest(vcpu);



	do {

		/* Jump in the fire! */

		exit_code = __guest_enter(vcpu, host_ctxt);



		/* And we're baaack! */

	} while (fixup_guest_exit(vcpu, &exit_code));



	fp_enabled = __fpsimd_enabled();



	__sysreg_save_guest_state(guest_ctxt);

	__sysreg32_save_state(vcpu);

	__timer_disable_traps(vcpu);

	__vgic_save_state(vcpu);



	__deactivate_traps(vcpu);

	__deactivate_vm(vcpu);



	__sysreg_restore_host_state(host_ctxt);



	if (fp_enabled) {

		__fpsimd_save_state(&guest_ctxt->gp_regs.fp_regs);

		__fpsimd_restore_state(&host_ctxt->gp_regs.fp_regs);

	}



	/*

	 * This must come after restoring the host sysregs, since a non-VHE

	 * system may enable SPE here and make use of the TTBRs.

	 */

	__debug_switch_to_host(vcpu);



	return exit_code;

}



/* Switch to the guest for legacy non-VHE systems */

int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)

{

	struct kvm_cpu_context *host_ctxt;

	struct kvm_cpu_context *guest_ctxt;