Commit | Line | Data |
---|---|---|
c4b1afd0 MZ |
1 | /* |
2 | * Copyright (C) 2012,2013 - ARM Ltd | |
3 | * Author: Marc Zyngier <marc.zyngier@arm.com> | |
4 | * | |
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> | |
8 | * | |
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. | |
12 | * | |
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. | |
17 | * | |
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/>. | |
20 | */ | |
21 | ||
22 | #include <linux/kvm.h> | |
23 | #include <linux/kvm_host.h> | |
c6d01a94 | 24 | |
1a2fb94e MZ |
25 | #include <kvm/arm_psci.h> |
26 | ||
c6d01a94 | 27 | #include <asm/esr.h> |
0067df41 | 28 | #include <asm/exception.h> |
9d8415d6 | 29 | #include <asm/kvm_asm.h> |
c4b1afd0 | 30 | #include <asm/kvm_coproc.h> |
c6d01a94 | 31 | #include <asm/kvm_emulate.h> |
c4b1afd0 | 32 | #include <asm/kvm_mmu.h> |
e70dce73 | 33 | #include <asm/debug-monitors.h> |
3368bd80 | 34 | #include <asm/traps.h> |
c4b1afd0 | 35 | |
0d97f884 WH |
36 | #define CREATE_TRACE_POINTS |
37 | #include "trace.h" | |
38 | ||
c4b1afd0 MZ |
39 | typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *); |
40 | ||
3368bd80 JM |
41 | static void kvm_handle_guest_serror(struct kvm_vcpu *vcpu, u32 esr) |
42 | { | |
43 | if (!arm64_is_ras_serror(esr) || arm64_is_fatal_ras_serror(NULL, esr)) | |
44 | kvm_inject_vabt(vcpu); | |
45 | } | |
46 | ||
c4b1afd0 MZ |
47 | static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) |
48 | { | |
e8e7fcc5 AP |
49 | int ret; |
50 | ||
f6be563a | 51 | trace_kvm_hvc_arm64(*vcpu_pc(vcpu), vcpu_get_reg(vcpu, 0), |
0d97f884 | 52 | kvm_vcpu_hvc_get_imm(vcpu)); |
b19e6892 | 53 | vcpu->stat.hvc_exit_stat++; |
0d97f884 | 54 | |
09e6be12 | 55 | ret = kvm_hvc_call_handler(vcpu); |
e8e7fcc5 | 56 | if (ret < 0) { |
c0938c72 | 57 | vcpu_set_reg(vcpu, 0, ~0UL); |
dcd2e40c | 58 | return 1; |
e8e7fcc5 | 59 | } |
dcd2e40c | 60 | |
e8e7fcc5 | 61 | return ret; |
c4b1afd0 MZ |
62 | } |
63 | ||
64 | static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) | |
65 | { | |
f5115e88 MZ |
66 | /* |
67 | * "If an SMC instruction executed at Non-secure EL1 is | |
68 | * trapped to EL2 because HCR_EL2.TSC is 1, the exception is a | |
69 | * Trap exception, not a Secure Monitor Call exception [...]" | |
70 | * | |
71 | * We need to advance the PC after the trap, as it would | |
72 | * otherwise return to the same address... | |
73 | */ | |
c0938c72 | 74 | vcpu_set_reg(vcpu, 0, ~0UL); |
f5115e88 | 75 | kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); |
c4b1afd0 MZ |
76 | return 1; |
77 | } | |
78 | ||
82e0191a SP |
79 | /* |
80 | * Guest access to FP/ASIMD registers are routed to this handler only | |
81 | * when the system doesn't support FP/ASIMD. | |
82 | */ | |
83 | static int handle_no_fpsimd(struct kvm_vcpu *vcpu, struct kvm_run *run) | |
84 | { | |
85 | kvm_inject_undefined(vcpu); | |
86 | return 1; | |
87 | } | |
88 | ||
c4b1afd0 | 89 | /** |
d241aac7 MZ |
90 | * kvm_handle_wfx - handle a wait-for-interrupts or wait-for-event |
91 | * instruction executed by a guest | |
92 | * | |
c4b1afd0 MZ |
93 | * @vcpu: the vcpu pointer |
94 | * | |
d241aac7 MZ |
95 | * WFE: Yield the CPU and come back to this vcpu when the scheduler |
96 | * decides to. | |
97 | * WFI: Simply call kvm_vcpu_block(), which will halt execution of | |
c4b1afd0 MZ |
98 | * world-switches and schedule other host processes until there is an |
99 | * incoming IRQ or FIQ to the VM. | |
100 | */ | |
d241aac7 | 101 | static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run) |
c4b1afd0 | 102 | { |
1c6007d5 | 103 | if (kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WFx_ISS_WFE) { |
0d97f884 | 104 | trace_kvm_wfx_arm64(*vcpu_pc(vcpu), true); |
b19e6892 | 105 | vcpu->stat.wfe_exit_stat++; |
f01fbd2f | 106 | kvm_vcpu_on_spin(vcpu, vcpu_mode_priv(vcpu)); |
0d97f884 WH |
107 | } else { |
108 | trace_kvm_wfx_arm64(*vcpu_pc(vcpu), false); | |
b19e6892 | 109 | vcpu->stat.wfi_exit_stat++; |
d241aac7 | 110 | kvm_vcpu_block(vcpu); |
6a6d73be | 111 | kvm_clear_request(KVM_REQ_UNHALT, vcpu); |
0d97f884 | 112 | } |
d241aac7 | 113 | |
05e0127f CD |
114 | kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); |
115 | ||
c4b1afd0 MZ |
116 | return 1; |
117 | } | |
118 | ||
4bd611ca AB |
119 | /** |
120 | * kvm_handle_guest_debug - handle a debug exception instruction | |
121 | * | |
122 | * @vcpu: the vcpu pointer | |
123 | * @run: access to the kvm_run structure for results | |
124 | * | |
125 | * We route all debug exceptions through the same handler. If both the | |
126 | * guest and host are using the same debug facilities it will be up to | |
127 | * userspace to re-inject the correct exception for guest delivery. | |
128 | * | |
129 | * @return: 0 (while setting run->exit_reason), -1 for error | |
130 | */ | |
131 | static int kvm_handle_guest_debug(struct kvm_vcpu *vcpu, struct kvm_run *run) | |
132 | { | |
133 | u32 hsr = kvm_vcpu_get_hsr(vcpu); | |
134 | int ret = 0; | |
135 | ||
136 | run->exit_reason = KVM_EXIT_DEBUG; | |
137 | run->debug.arch.hsr = hsr; | |
138 | ||
561454e2 | 139 | switch (ESR_ELx_EC(hsr)) { |
834bf887 AB |
140 | case ESR_ELx_EC_WATCHPT_LOW: |
141 | run->debug.arch.far = vcpu->arch.fault.far_el2; | |
142 | /* fall through */ | |
337b99bf | 143 | case ESR_ELx_EC_SOFTSTP_LOW: |
834bf887 | 144 | case ESR_ELx_EC_BREAKPT_LOW: |
4bd611ca AB |
145 | case ESR_ELx_EC_BKPT32: |
146 | case ESR_ELx_EC_BRK64: | |
147 | break; | |
148 | default: | |
149 | kvm_err("%s: un-handled case hsr: %#08x\n", | |
150 | __func__, (unsigned int) hsr); | |
151 | ret = -1; | |
152 | break; | |
153 | } | |
154 | ||
155 | return ret; | |
156 | } | |
157 | ||
ba4dd156 MR |
158 | static int kvm_handle_unknown_ec(struct kvm_vcpu *vcpu, struct kvm_run *run) |
159 | { | |
160 | u32 hsr = kvm_vcpu_get_hsr(vcpu); | |
161 | ||
162 | kvm_pr_unimpl("Unknown exception class: hsr: %#08x -- %s\n", | |
163 | hsr, esr_get_class_string(hsr)); | |
164 | ||
165 | kvm_inject_undefined(vcpu); | |
166 | return 1; | |
167 | } | |
168 | ||
aac45ffd DM |
169 | static int handle_sve(struct kvm_vcpu *vcpu, struct kvm_run *run) |
170 | { | |
171 | /* Until SVE is supported for guests: */ | |
172 | kvm_inject_undefined(vcpu); | |
173 | return 1; | |
174 | } | |
175 | ||
384b40ca MR |
176 | #define __ptrauth_save_key(regs, key) \ |
177 | ({ \ | |
178 | regs[key ## KEYLO_EL1] = read_sysreg_s(SYS_ ## key ## KEYLO_EL1); \ | |
179 | regs[key ## KEYHI_EL1] = read_sysreg_s(SYS_ ## key ## KEYHI_EL1); \ | |
180 | }) | |
181 | ||
182 | /* | |
183 | * Handle the guest trying to use a ptrauth instruction, or trying to access a | |
184 | * ptrauth register. | |
185 | */ | |
186 | void kvm_arm_vcpu_ptrauth_trap(struct kvm_vcpu *vcpu) | |
187 | { | |
188 | struct kvm_cpu_context *ctxt; | |
189 | ||
190 | if (vcpu_has_ptrauth(vcpu)) { | |
191 | vcpu_ptrauth_enable(vcpu); | |
192 | ctxt = vcpu->arch.host_cpu_context; | |
193 | __ptrauth_save_key(ctxt->sys_regs, APIA); | |
194 | __ptrauth_save_key(ctxt->sys_regs, APIB); | |
195 | __ptrauth_save_key(ctxt->sys_regs, APDA); | |
196 | __ptrauth_save_key(ctxt->sys_regs, APDB); | |
197 | __ptrauth_save_key(ctxt->sys_regs, APGA); | |
198 | } else { | |
199 | kvm_inject_undefined(vcpu); | |
200 | } | |
201 | } | |
202 | ||
a1ee8abb MR |
203 | /* |
204 | * Guest usage of a ptrauth instruction (which the guest EL1 did not turn into | |
205 | * a NOP). | |
206 | */ | |
207 | static int kvm_handle_ptrauth(struct kvm_vcpu *vcpu, struct kvm_run *run) | |
208 | { | |
384b40ca | 209 | kvm_arm_vcpu_ptrauth_trap(vcpu); |
a1ee8abb MR |
210 | return 1; |
211 | } | |
212 | ||
c4b1afd0 | 213 | static exit_handle_fn arm_exit_handlers[] = { |
ba4dd156 | 214 | [0 ... ESR_ELx_EC_MAX] = kvm_handle_unknown_ec, |
c6d01a94 MR |
215 | [ESR_ELx_EC_WFx] = kvm_handle_wfx, |
216 | [ESR_ELx_EC_CP15_32] = kvm_handle_cp15_32, | |
217 | [ESR_ELx_EC_CP15_64] = kvm_handle_cp15_64, | |
218 | [ESR_ELx_EC_CP14_MR] = kvm_handle_cp14_32, | |
219 | [ESR_ELx_EC_CP14_LS] = kvm_handle_cp14_load_store, | |
220 | [ESR_ELx_EC_CP14_64] = kvm_handle_cp14_64, | |
221 | [ESR_ELx_EC_HVC32] = handle_hvc, | |
222 | [ESR_ELx_EC_SMC32] = handle_smc, | |
223 | [ESR_ELx_EC_HVC64] = handle_hvc, | |
224 | [ESR_ELx_EC_SMC64] = handle_smc, | |
225 | [ESR_ELx_EC_SYS64] = kvm_handle_sys_reg, | |
aac45ffd | 226 | [ESR_ELx_EC_SVE] = handle_sve, |
c6d01a94 MR |
227 | [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort, |
228 | [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort, | |
337b99bf | 229 | [ESR_ELx_EC_SOFTSTP_LOW]= kvm_handle_guest_debug, |
834bf887 AB |
230 | [ESR_ELx_EC_WATCHPT_LOW]= kvm_handle_guest_debug, |
231 | [ESR_ELx_EC_BREAKPT_LOW]= kvm_handle_guest_debug, | |
4bd611ca AB |
232 | [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug, |
233 | [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug, | |
82e0191a | 234 | [ESR_ELx_EC_FP_ASIMD] = handle_no_fpsimd, |
a1ee8abb | 235 | [ESR_ELx_EC_PAC] = kvm_handle_ptrauth, |
c4b1afd0 MZ |
236 | }; |
237 | ||
238 | static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu) | |
239 | { | |
056bb5f5 | 240 | u32 hsr = kvm_vcpu_get_hsr(vcpu); |
561454e2 | 241 | u8 hsr_ec = ESR_ELx_EC(hsr); |
c4b1afd0 | 242 | |
c4b1afd0 MZ |
243 | return arm_exit_handlers[hsr_ec]; |
244 | } | |
245 | ||
7226bc2e AB |
246 | /* |
247 | * We may be single-stepping an emulated instruction. If the emulation | |
248 | * has been completed in the kernel, we can return to userspace with a | |
249 | * KVM_EXIT_DEBUG, otherwise userspace needs to complete its | |
250 | * emulation first. | |
251 | */ | |
252 | static int handle_trap_exceptions(struct kvm_vcpu *vcpu, struct kvm_run *run) | |
253 | { | |
254 | int handled; | |
255 | ||
256 | /* | |
257 | * See ARM ARM B1.14.1: "Hyp traps on instructions | |
258 | * that fail their condition code check" | |
259 | */ | |
260 | if (!kvm_condition_valid(vcpu)) { | |
261 | kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); | |
262 | handled = 1; | |
263 | } else { | |
264 | exit_handle_fn exit_handler; | |
265 | ||
266 | exit_handler = kvm_get_exit_handler(vcpu); | |
267 | handled = exit_handler(vcpu, run); | |
268 | } | |
269 | ||
7226bc2e AB |
270 | return handled; |
271 | } | |
272 | ||
c4b1afd0 MZ |
273 | /* |
274 | * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on | |
275 | * proper exit to userspace. | |
276 | */ | |
277 | int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, | |
278 | int exception_index) | |
279 | { | |
ddb3d07c MZ |
280 | if (ARM_SERROR_PENDING(exception_index)) { |
281 | u8 hsr_ec = ESR_ELx_EC(kvm_vcpu_get_hsr(vcpu)); | |
282 | ||
283 | /* | |
284 | * HVC/SMC already have an adjusted PC, which we need | |
285 | * to correct in order to return to after having | |
286 | * injected the SError. | |
287 | */ | |
288 | if (hsr_ec == ESR_ELx_EC_HVC32 || hsr_ec == ESR_ELx_EC_HVC64 || | |
289 | hsr_ec == ESR_ELx_EC_SMC32 || hsr_ec == ESR_ELx_EC_SMC64) { | |
290 | u32 adj = kvm_vcpu_trap_il_is32bit(vcpu) ? 4 : 2; | |
291 | *vcpu_pc(vcpu) -= adj; | |
292 | } | |
293 | ||
ddb3d07c MZ |
294 | return 1; |
295 | } | |
296 | ||
297 | exception_index = ARM_EXCEPTION_CODE(exception_index); | |
298 | ||
c4b1afd0 MZ |
299 | switch (exception_index) { |
300 | case ARM_EXCEPTION_IRQ: | |
301 | return 1; | |
0215a6e6 | 302 | case ARM_EXCEPTION_EL1_SERROR: |
bd7d95ca | 303 | return 1; |
c4b1afd0 | 304 | case ARM_EXCEPTION_TRAP: |
7226bc2e | 305 | return handle_trap_exceptions(vcpu, run); |
c94b0cf2 JM |
306 | case ARM_EXCEPTION_HYP_GONE: |
307 | /* | |
308 | * EL2 has been reset to the hyp-stub. This happens when a guest | |
309 | * is pre-empted by kvm_reboot()'s shutdown call. | |
310 | */ | |
311 | run->exit_reason = KVM_EXIT_FAIL_ENTRY; | |
312 | return 0; | |
e4e11cc0 CD |
313 | case ARM_EXCEPTION_IL: |
314 | /* | |
315 | * We attempted an illegal exception return. Guest state must | |
316 | * have been corrupted somehow. Give up. | |
317 | */ | |
318 | run->exit_reason = KVM_EXIT_FAIL_ENTRY; | |
319 | return -EINVAL; | |
c4b1afd0 MZ |
320 | default: |
321 | kvm_pr_unimpl("Unsupported exception type: %d", | |
322 | exception_index); | |
323 | run->exit_reason = KVM_EXIT_INTERNAL_ERROR; | |
324 | return 0; | |
325 | } | |
326 | } | |
3368bd80 JM |
327 | |
328 | /* For exit types that need handling before we can be preempted */ | |
329 | void handle_exit_early(struct kvm_vcpu *vcpu, struct kvm_run *run, | |
330 | int exception_index) | |
331 | { | |
0067df41 JM |
332 | if (ARM_SERROR_PENDING(exception_index)) { |
333 | if (this_cpu_has_cap(ARM64_HAS_RAS_EXTN)) { | |
334 | u64 disr = kvm_vcpu_get_disr(vcpu); | |
335 | ||
336 | kvm_handle_guest_serror(vcpu, disr_to_esr(disr)); | |
337 | } else { | |
338 | kvm_inject_vabt(vcpu); | |
339 | } | |
340 | ||
341 | return; | |
342 | } | |
343 | ||
3368bd80 JM |
344 | exception_index = ARM_EXCEPTION_CODE(exception_index); |
345 | ||
346 | if (exception_index == ARM_EXCEPTION_EL1_SERROR) | |
347 | kvm_handle_guest_serror(vcpu, kvm_vcpu_get_hsr(vcpu)); | |
348 | } |