1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#include <hyp/switch.h>
#include <linux/arm-smccc.h>
#include <linux/kvm_host.h>
#include <linux/types.h>
#include <linux/jump_label.h>
#include <uapi/linux/psci.h>
#include <kvm/arm_psci.h>
#include <asm/barrier.h>
#include <asm/cpufeature.h>
#include <asm/kprobes.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_hyp.h>
#include <asm/kvm_mmu.h>
#include <asm/fpsimd.h>
#include <asm/debug-monitors.h>
#include <asm/processor.h>
#include <asm/thread_info.h>
const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n";
static void __activate_traps(struct kvm_vcpu *vcpu)
{
u64 val;
___activate_traps(vcpu);
val = read_sysreg(cpacr_el1);
val |= CPACR_EL1_TTA;
val &= ~CPACR_EL1_ZEN;
/*
* With VHE (HCR.E2H == 1), accesses to CPACR_EL1 are routed to
* CPTR_EL2. In general, CPACR_EL1 has the same layout as CPTR_EL2,
* except for some missing controls, such as TAM.
* In this case, CPTR_EL2.TAM has the same position with or without
* VHE (HCR.E2H == 1) which allows us to use here the CPTR_EL2.TAM
* shift value for trapping the AMU accesses.
*/
val |= CPTR_EL2_TAM;
if (update_fp_enabled(vcpu)) {
if (vcpu_has_sve(vcpu))
val |= CPACR_EL1_ZEN;
} else {
val &= ~CPACR_EL1_FPEN;
__activate_traps_fpsimd32(vcpu);
}
write_sysreg(val, cpacr_el1);
write_sysreg(kvm_get_hyp_vector(), vbar_el1);
}
NOKPROBE_SYMBOL(__activate_traps);
static void __deactivate_traps(struct kvm_vcpu *vcpu)
{
extern char vectors[]; /* kernel exception vectors */
___deactivate_traps(vcpu);
write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
/*
* ARM errata 1165522 and 1530923 require the actual execution of the
* above before we can switch to the EL2/EL0 translation regime used by
* the host.
*/
asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1);
write_sysreg(vectors, vbar_el1);
}
NOKPROBE_SYMBOL(__deactivate_traps);
void activate_traps_vhe_load(struct kvm_vcpu *vcpu)
{
__activate_traps_common(vcpu);
}
void deactivate_traps_vhe_put(void)
{
u64 mdcr_el2 = read_sysreg(mdcr_el2);
mdcr_el2 &= MDCR_EL2_HPMN_MASK |
MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT |
MDCR_EL2_TPMS;
write_sysreg(mdcr_el2, mdcr_el2);
__deactivate_traps_common();
}
/* Switch to the guest for VHE systems running in EL2 */
static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_cpu_context *guest_ctxt;
u64 exit_code;
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt->__hyp_running_vcpu = vcpu;
guest_ctxt = &vcpu->arch.ctxt;
sysreg_save_host_state_vhe(host_ctxt);
/*
* ARM erratum 1165522 requires us to configure both stage 1 and
* stage 2 translation for the guest context before we clear
* HCR_EL2.TGE.
*
* We have already configured the guest's stage 1 translation in
* kvm_vcpu_load_sysregs_vhe above. We must now call __activate_vm
* before __activate_traps, because __activate_vm configures
* stage 2 translation, and __activate_traps clear HCR_EL2.TGE
* (among other things).
*/
__activate_vm(vcpu->arch.hw_mmu);
__activate_traps(vcpu);
sysreg_restore_guest_state_vhe(guest_ctxt);
__debug_switch_to_guest(vcpu);
__set_guest_arch_workaround_state(vcpu);
do {
/* Jump in the fire! */
exit_code = __guest_enter(vcpu, host_ctxt);
/* And we're baaack! */
} while (fixup_guest_exit(vcpu, &exit_code));
__set_host_arch_workaround_state(vcpu);
sysreg_save_guest_state_vhe(guest_ctxt);
__deactivate_traps(vcpu);
sysreg_restore_host_state_vhe(host_ctxt);
if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED)
__fpsimd_save_fpexc32(vcpu);
__debug_switch_to_host(vcpu);
return exit_code;
}
NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe);
int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
{
int ret;
local_daif_mask();
/*
* Having IRQs masked via PMR when entering the guest means the GIC
* will not signal the CPU of interrupts of lower priority, and the
* only way to get out will be via guest exceptions.
* Naturally, we want to avoid this.
*
* local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a
* dsb to ensure the redistributor is forwards EL2 IRQs to the CPU.
*/
pmr_sync();
ret = __kvm_vcpu_run_vhe(vcpu);
/*
* local_daif_restore() takes care to properly restore PSTATE.DAIF
* and the GIC PMR if the host is using IRQ priorities.
*/
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();
return ret;
}
static void __hyp_call_panic(u64 spsr, u64 elr, u64 par,
struct kvm_cpu_context *host_ctxt)
{
struct kvm_vcpu *vcpu;
vcpu = host_ctxt->__hyp_running_vcpu;
__deactivate_traps(vcpu);
sysreg_restore_host_state_vhe(host_ctxt);
panic(__hyp_panic_string,
spsr, elr,
read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR),
read_sysreg(hpfar_el2), par, vcpu);
}
NOKPROBE_SYMBOL(__hyp_call_panic);
void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt)
{
u64 spsr = read_sysreg_el2(SYS_SPSR);
u64 elr = read_sysreg_el2(SYS_ELR);
u64 par = read_sysreg(par_el1);
__hyp_call_panic(spsr, elr, par, host_ctxt);
unreachable();
}
|
