2 * Copyright (C) 2012,2013 - ARM Ltd
3 * Author: Marc Zyngier <marc.zyngier@arm.com>
5 * Derived from arch/arm/kvm/handle_exit.c:
6 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
7 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include <linux/kvm.h>
23 #include <linux/kvm_host.h>
26 #include <asm/kvm_asm.h>
27 #include <asm/kvm_coproc.h>
28 #include <asm/kvm_emulate.h>
29 #include <asm/kvm_mmu.h>
30 #include <asm/kvm_psci.h>
32 #define CREATE_TRACE_POINTS
35 typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);
37 static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
41 trace_kvm_hvc_arm64(*vcpu_pc(vcpu), vcpu_get_reg(vcpu, 0),
42 kvm_vcpu_hvc_get_imm(vcpu));
43 vcpu->stat.hvc_exit_stat++;
45 ret = kvm_psci_call(vcpu);
47 kvm_inject_undefined(vcpu);
54 static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
56 kvm_inject_undefined(vcpu);
61 * Guest access to FP/ASIMD registers are routed to this handler only
62 * when the system doesn't support FP/ASIMD.
64 static int handle_no_fpsimd(struct kvm_vcpu *vcpu, struct kvm_run *run)
66 kvm_inject_undefined(vcpu);
71 * kvm_handle_wfx - handle a wait-for-interrupts or wait-for-event
72 * instruction executed by a guest
74 * @vcpu: the vcpu pointer
76 * WFE: Yield the CPU and come back to this vcpu when the scheduler
78 * WFI: Simply call kvm_vcpu_block(), which will halt execution of
79 * world-switches and schedule other host processes until there is an
80 * incoming IRQ or FIQ to the VM.
82 static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run)
84 if (kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WFx_ISS_WFE) {
85 trace_kvm_wfx_arm64(*vcpu_pc(vcpu), true);
86 vcpu->stat.wfe_exit_stat++;
87 kvm_vcpu_on_spin(vcpu);
89 trace_kvm_wfx_arm64(*vcpu_pc(vcpu), false);
90 vcpu->stat.wfi_exit_stat++;
94 kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
100 * kvm_handle_guest_debug - handle a debug exception instruction
102 * @vcpu: the vcpu pointer
103 * @run: access to the kvm_run structure for results
105 * We route all debug exceptions through the same handler. If both the
106 * guest and host are using the same debug facilities it will be up to
107 * userspace to re-inject the correct exception for guest delivery.
109 * @return: 0 (while setting run->exit_reason), -1 for error
111 static int kvm_handle_guest_debug(struct kvm_vcpu *vcpu, struct kvm_run *run)
113 u32 hsr = kvm_vcpu_get_hsr(vcpu);
116 run->exit_reason = KVM_EXIT_DEBUG;
117 run->debug.arch.hsr = hsr;
119 switch (ESR_ELx_EC(hsr)) {
120 case ESR_ELx_EC_WATCHPT_LOW:
121 run->debug.arch.far = vcpu->arch.fault.far_el2;
123 case ESR_ELx_EC_SOFTSTP_LOW:
124 case ESR_ELx_EC_BREAKPT_LOW:
125 case ESR_ELx_EC_BKPT32:
126 case ESR_ELx_EC_BRK64:
129 kvm_err("%s: un-handled case hsr: %#08x\n",
130 __func__, (unsigned int) hsr);
138 static int kvm_handle_unknown_ec(struct kvm_vcpu *vcpu, struct kvm_run *run)
140 u32 hsr = kvm_vcpu_get_hsr(vcpu);
142 kvm_pr_unimpl("Unknown exception class: hsr: %#08x -- %s\n",
143 hsr, esr_get_class_string(hsr));
145 kvm_inject_undefined(vcpu);
149 static exit_handle_fn arm_exit_handlers[] = {
150 [0 ... ESR_ELx_EC_MAX] = kvm_handle_unknown_ec,
151 [ESR_ELx_EC_WFx] = kvm_handle_wfx,
152 [ESR_ELx_EC_CP15_32] = kvm_handle_cp15_32,
153 [ESR_ELx_EC_CP15_64] = kvm_handle_cp15_64,
154 [ESR_ELx_EC_CP14_MR] = kvm_handle_cp14_32,
155 [ESR_ELx_EC_CP14_LS] = kvm_handle_cp14_load_store,
156 [ESR_ELx_EC_CP14_64] = kvm_handle_cp14_64,
157 [ESR_ELx_EC_HVC32] = handle_hvc,
158 [ESR_ELx_EC_SMC32] = handle_smc,
159 [ESR_ELx_EC_HVC64] = handle_hvc,
160 [ESR_ELx_EC_SMC64] = handle_smc,
161 [ESR_ELx_EC_SYS64] = kvm_handle_sys_reg,
162 [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort,
163 [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort,
164 [ESR_ELx_EC_SOFTSTP_LOW]= kvm_handle_guest_debug,
165 [ESR_ELx_EC_WATCHPT_LOW]= kvm_handle_guest_debug,
166 [ESR_ELx_EC_BREAKPT_LOW]= kvm_handle_guest_debug,
167 [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug,
168 [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug,
169 [ESR_ELx_EC_FP_ASIMD] = handle_no_fpsimd,
172 static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
174 u32 hsr = kvm_vcpu_get_hsr(vcpu);
175 u8 hsr_ec = ESR_ELx_EC(hsr);
177 return arm_exit_handlers[hsr_ec];
181 * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
182 * proper exit to userspace.
184 int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
187 exit_handle_fn exit_handler;
189 if (ARM_SERROR_PENDING(exception_index)) {
190 u8 hsr_ec = ESR_ELx_EC(kvm_vcpu_get_hsr(vcpu));
193 * HVC/SMC already have an adjusted PC, which we need
194 * to correct in order to return to after having
195 * injected the SError.
197 if (hsr_ec == ESR_ELx_EC_HVC32 || hsr_ec == ESR_ELx_EC_HVC64 ||
198 hsr_ec == ESR_ELx_EC_SMC32 || hsr_ec == ESR_ELx_EC_SMC64) {
199 u32 adj = kvm_vcpu_trap_il_is32bit(vcpu) ? 4 : 2;
200 *vcpu_pc(vcpu) -= adj;
203 kvm_inject_vabt(vcpu);
207 exception_index = ARM_EXCEPTION_CODE(exception_index);
209 switch (exception_index) {
210 case ARM_EXCEPTION_IRQ:
212 case ARM_EXCEPTION_EL1_SERROR:
213 kvm_inject_vabt(vcpu);
215 case ARM_EXCEPTION_TRAP:
217 * See ARM ARM B1.14.1: "Hyp traps on instructions
218 * that fail their condition code check"
220 if (!kvm_condition_valid(vcpu)) {
221 kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
225 exit_handler = kvm_get_exit_handler(vcpu);
227 return exit_handler(vcpu, run);
228 case ARM_EXCEPTION_HYP_GONE:
230 * EL2 has been reset to the hyp-stub. This happens when a guest
231 * is pre-empted by kvm_reboot()'s shutdown call.
233 run->exit_reason = KVM_EXIT_FAIL_ENTRY;
236 kvm_pr_unimpl("Unsupported exception type: %d",
238 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;