Commit eeeee719 authored by David Brazdil's avatar David Brazdil Committed by Marc Zyngier
Browse files

KVM: arm64: Bootstrap PSCI SMC handler in nVHE EL2 



Add a handler of PSCI SMCs in nVHE hyp code. The handler is initialized
with the version used by the host's PSCI driver and the function IDs it
was configured with. If the SMC function ID matches one of the
configured PSCI calls (for v0.1) or falls into the PSCI function ID
range (for v0.2+), the SMC is handled by the PSCI handler. For now, all
SMCs return PSCI_RET_NOT_SUPPORTED.

Signed-off-by: default avatarDavid Brazdil <dbrazdil@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201202184122.26046-17-dbrazdil@google.com
parent a805e1fb

arch/arm64/include/asm/kvm_hyp.h

+2 −0
Original line number Diff line number Diff line
@@ -93,6 +93,8 @@ void deactivate_traps_vhe_put(void); 


u64 __guest_enter(struct kvm_vcpu *vcpu);



bool kvm_host_psci_handler(struct kvm_cpu_context *host_ctxt);



void __noreturn hyp_panic(void);

#ifdef __KVM_NVHE_HYPERVISOR__

void __noreturn __hyp_do_panic(bool restore_host, u64 spsr, u64 elr, u64 par);

arch/arm64/kvm/arm.c

+24 −1
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
#include <linux/kvm_irqfd.h>

#include <linux/irqbypass.h>

#include <linux/sched/stat.h>

#include <linux/psci.h>

#include <trace/events/kvm.h>



#define CREATE_TRACE_POINTS
@@ -65,6 +66,8 @@ static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled); 
DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);



extern u64 kvm_nvhe_sym(__cpu_logical_map)[NR_CPUS];

extern u32 kvm_nvhe_sym(kvm_host_psci_version);

extern struct psci_0_1_function_ids kvm_nvhe_sym(kvm_host_psci_0_1_function_ids);



int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)

{
@@ -1522,6 +1525,22 @@ static void init_cpu_logical_map(void) 
		kvm_nvhe_sym(__cpu_logical_map)[cpu] = cpu_logical_map(cpu);

}



static bool init_psci_relay(void)

{

	/*

	 * If PSCI has not been initialized, protected KVM cannot install

	 * itself on newly booted CPUs.

	 */

	if (!psci_ops.get_version) {

		kvm_err("Cannot initialize protected mode without PSCI\n");

		return false;

	}



	kvm_nvhe_sym(kvm_host_psci_version) = psci_ops.get_version();

	kvm_nvhe_sym(kvm_host_psci_0_1_function_ids) = get_psci_0_1_function_ids();

	return true;

}



static int init_common_resources(void)

{

	return kvm_set_ipa_limit();
@@ -1700,9 +1719,13 @@ static int init_hyp_mode(void) 
		}

	}



	if (is_protected_kvm_enabled())

	if (is_protected_kvm_enabled()) {

		init_cpu_logical_map();



		if (!init_psci_relay())

			goto out_err;

	}



	return 0;



out_err:

arch/arm64/kvm/hyp/include/nvhe/trap_handler.h

0 → 100644
+18 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Trap handler helpers.

 *

 * Copyright (C) 2020 - Google LLC

 * Author: Marc Zyngier <maz@kernel.org>

 */



#ifndef __ARM64_KVM_NVHE_TRAP_HANDLER_H__

#define __ARM64_KVM_NVHE_TRAP_HANDLER_H__



#include <asm/kvm_host.h>



#define cpu_reg(ctxt, r)	(ctxt)->regs.regs[r]

#define DECLARE_REG(type, name, ctxt, reg)	\

				type name = (type)cpu_reg(ctxt, (reg))



#endif /* __ARM64_KVM_NVHE_TRAP_HANDLER_H__ */

arch/arm64/kvm/hyp/nvhe/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ asflags-y := -D__KVM_NVHE_HYPERVISOR__ 
ccflags-y := -D__KVM_NVHE_HYPERVISOR__



obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \

	 hyp-main.o hyp-smp.o

	 hyp-main.o hyp-smp.o psci-relay.o

obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \

	 ../fpsimd.o ../hyp-entry.o

arch/arm64/kvm/hyp/nvhe/hyp-main.c

+6 −4
Original line number Diff line number Diff line
@@ -12,9 +12,7 @@ 
#include <asm/kvm_hyp.h>

#include <asm/kvm_mmu.h>



#define cpu_reg(ctxt, r)	(ctxt)->regs.regs[r]

#define DECLARE_REG(type, name, ctxt, reg)	\

				type name = (type)cpu_reg(ctxt, (reg))

#include <nvhe/trap_handler.h>



DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
@@ -166,6 +164,10 @@ static void skip_host_instruction(void) 


static void handle_host_smc(struct kvm_cpu_context *host_ctxt)

{

	bool handled;



	handled = kvm_host_psci_handler(host_ctxt);

	if (!handled)

		default_host_smc_handler(host_ctxt);



	/*

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