1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2015 - ARM Ltd
4 * Author: Marc Zyngier <marc.zyngier@arm.com>
7 #include <hyp/switch.h>
9 #include <linux/arm-smccc.h>
10 #include <linux/kvm_host.h>
11 #include <linux/types.h>
12 #include <linux/jump_label.h>
13 #include <linux/percpu.h>
14 #include <uapi/linux/psci.h>
16 #include <kvm/arm_psci.h>
18 #include <asm/barrier.h>
19 #include <asm/cpufeature.h>
20 #include <asm/kprobes.h>
21 #include <asm/kvm_asm.h>
22 #include <asm/kvm_emulate.h>
23 #include <asm/kvm_hyp.h>
24 #include <asm/kvm_mmu.h>
25 #include <asm/fpsimd.h>
26 #include <asm/debug-monitors.h>
27 #include <asm/processor.h>
28 #include <asm/thread_info.h>
29 #include <asm/vectors.h>
31 /* VHE specific context */
32 DEFINE_PER_CPU(struct kvm_host_data, kvm_host_data);
33 DEFINE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
34 DEFINE_PER_CPU(unsigned long, kvm_hyp_vector);
36 static void __activate_traps(struct kvm_vcpu *vcpu)
40 ___activate_traps(vcpu);
42 val = read_sysreg(cpacr_el1);
44 val &= ~(CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN |
45 CPACR_EL1_SMEN_EL0EN | CPACR_EL1_SMEN_EL1EN);
48 * With VHE (HCR.E2H == 1), accesses to CPACR_EL1 are routed to
49 * CPTR_EL2. In general, CPACR_EL1 has the same layout as CPTR_EL2,
50 * except for some missing controls, such as TAM.
51 * In this case, CPTR_EL2.TAM has the same position with or without
52 * VHE (HCR.E2H == 1) which allows us to use here the CPTR_EL2.TAM
53 * shift value for trapping the AMU accesses.
58 if (guest_owns_fp_regs(vcpu)) {
59 if (vcpu_has_sve(vcpu))
60 val |= CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN;
62 val &= ~(CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN);
63 __activate_traps_fpsimd32(vcpu);
66 write_sysreg(val, cpacr_el1);
68 write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el1);
70 NOKPROBE_SYMBOL(__activate_traps);
72 static void __deactivate_traps(struct kvm_vcpu *vcpu)
74 const char *host_vectors = vectors;
76 ___deactivate_traps(vcpu);
78 write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
81 * ARM errata 1165522 and 1530923 require the actual execution of the
82 * above before we can switch to the EL2/EL0 translation regime used by
85 asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
87 kvm_reset_cptr_el2(vcpu);
89 if (!arm64_kernel_unmapped_at_el0())
90 host_vectors = __this_cpu_read(this_cpu_vector);
91 write_sysreg(host_vectors, vbar_el1);
93 NOKPROBE_SYMBOL(__deactivate_traps);
96 * Disable IRQs in {activate,deactivate}_traps_vhe_{load,put}() to
97 * prevent a race condition between context switching of PMUSERENR_EL0
98 * in __{activate,deactivate}_traps_common() and IPIs that attempts to
99 * update PMUSERENR_EL0. See also kvm_set_pmuserenr().
101 void activate_traps_vhe_load(struct kvm_vcpu *vcpu)
105 local_irq_save(flags);
106 __activate_traps_common(vcpu);
107 local_irq_restore(flags);
110 void deactivate_traps_vhe_put(struct kvm_vcpu *vcpu)
114 local_irq_save(flags);
115 __deactivate_traps_common(vcpu);
116 local_irq_restore(flags);
119 static const exit_handler_fn hyp_exit_handlers[] = {
120 [0 ... ESR_ELx_EC_MAX] = NULL,
121 [ESR_ELx_EC_CP15_32] = kvm_hyp_handle_cp15_32,
122 [ESR_ELx_EC_SYS64] = kvm_hyp_handle_sysreg,
123 [ESR_ELx_EC_SVE] = kvm_hyp_handle_fpsimd,
124 [ESR_ELx_EC_FP_ASIMD] = kvm_hyp_handle_fpsimd,
125 [ESR_ELx_EC_IABT_LOW] = kvm_hyp_handle_iabt_low,
126 [ESR_ELx_EC_DABT_LOW] = kvm_hyp_handle_dabt_low,
127 [ESR_ELx_EC_WATCHPT_LOW] = kvm_hyp_handle_watchpt_low,
128 [ESR_ELx_EC_PAC] = kvm_hyp_handle_ptrauth,
131 static const exit_handler_fn *kvm_get_exit_handler_array(struct kvm_vcpu *vcpu)
133 return hyp_exit_handlers;
136 static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code)
139 * If we were in HYP context on entry, adjust the PSTATE view
140 * so that the usual helpers work correctly.
142 if (unlikely(vcpu_get_flag(vcpu, VCPU_HYP_CONTEXT))) {
143 u64 mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT);
147 mode = PSR_MODE_EL2t;
150 mode = PSR_MODE_EL2h;
154 *vcpu_cpsr(vcpu) &= ~(PSR_MODE_MASK | PSR_MODE32_BIT);
155 *vcpu_cpsr(vcpu) |= mode;
159 /* Switch to the guest for VHE systems running in EL2 */
160 static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
162 struct kvm_cpu_context *host_ctxt;
163 struct kvm_cpu_context *guest_ctxt;
166 host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
167 host_ctxt->__hyp_running_vcpu = vcpu;
168 guest_ctxt = &vcpu->arch.ctxt;
170 sysreg_save_host_state_vhe(host_ctxt);
173 * ARM erratum 1165522 requires us to configure both stage 1 and
174 * stage 2 translation for the guest context before we clear
177 * We have already configured the guest's stage 1 translation in
178 * kvm_vcpu_load_sysregs_vhe above. We must now call
179 * __load_stage2 before __activate_traps, because
180 * __load_stage2 configures stage 2 translation, and
181 * __activate_traps clear HCR_EL2.TGE (among other things).
183 __load_stage2(vcpu->arch.hw_mmu, vcpu->arch.hw_mmu->arch);
184 __activate_traps(vcpu);
186 __kvm_adjust_pc(vcpu);
188 sysreg_restore_guest_state_vhe(guest_ctxt);
189 __debug_switch_to_guest(vcpu);
191 if (is_hyp_ctxt(vcpu))
192 vcpu_set_flag(vcpu, VCPU_HYP_CONTEXT);
194 vcpu_clear_flag(vcpu, VCPU_HYP_CONTEXT);
197 /* Jump in the fire! */
198 exit_code = __guest_enter(vcpu);
200 /* And we're baaack! */
201 } while (fixup_guest_exit(vcpu, &exit_code));
203 sysreg_save_guest_state_vhe(guest_ctxt);
205 __deactivate_traps(vcpu);
207 sysreg_restore_host_state_vhe(host_ctxt);
209 if (vcpu->arch.fp_state == FP_STATE_GUEST_OWNED)
210 __fpsimd_save_fpexc32(vcpu);
212 __debug_switch_to_host(vcpu);
216 NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe);
218 int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
225 * Having IRQs masked via PMR when entering the guest means the GIC
226 * will not signal the CPU of interrupts of lower priority, and the
227 * only way to get out will be via guest exceptions.
228 * Naturally, we want to avoid this.
230 * local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a
231 * dsb to ensure the redistributor is forwards EL2 IRQs to the CPU.
235 ret = __kvm_vcpu_run_vhe(vcpu);
238 * local_daif_restore() takes care to properly restore PSTATE.DAIF
239 * and the GIC PMR if the host is using IRQ priorities.
241 local_daif_restore(DAIF_PROCCTX_NOIRQ);
244 * When we exit from the guest we change a number of CPU configuration
245 * parameters, such as traps. We rely on the isb() in kvm_call_hyp*()
246 * to make sure these changes take effect before running the host or
252 static void __hyp_call_panic(u64 spsr, u64 elr, u64 par)
254 struct kvm_cpu_context *host_ctxt;
255 struct kvm_vcpu *vcpu;
257 host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
258 vcpu = host_ctxt->__hyp_running_vcpu;
260 __deactivate_traps(vcpu);
261 sysreg_restore_host_state_vhe(host_ctxt);
263 panic("HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n",
265 read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR),
266 read_sysreg(hpfar_el2), par, vcpu);
268 NOKPROBE_SYMBOL(__hyp_call_panic);
270 void __noreturn hyp_panic(void)
272 u64 spsr = read_sysreg_el2(SYS_SPSR);
273 u64 elr = read_sysreg_el2(SYS_ELR);
274 u64 par = read_sysreg_par();
276 __hyp_call_panic(spsr, elr, par);
280 asmlinkage void kvm_unexpected_el2_exception(void)
282 __kvm_unexpected_el2_exception();