aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm64/kernel/entry-common.c
blob: fde59981445ca9a0845102c905a8520773f618bf (plain) (blame)
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
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
// SPDX-License-Identifier: GPL-2.0
/*
 * Exception handling code
 *
 * Copyright (C) 2019 ARM Ltd.
 */

#include <linux/context_tracking.h>
#include <linux/ptrace.h>
#include <linux/thread_info.h>

#include <asm/cpufeature.h>
#include <asm/daifflags.h>
#include <asm/esr.h>
#include <asm/exception.h>
#include <asm/kprobes.h>
#include <asm/mmu.h>
#include <asm/sysreg.h>

static void notrace el1_abort(struct pt_regs *regs, unsigned long esr)
{
	unsigned long far = read_sysreg(far_el1);

	local_daif_inherit(regs);
	far = untagged_addr(far);
	do_mem_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el1_abort);

static void notrace el1_pc(struct pt_regs *regs, unsigned long esr)
{
	unsigned long far = read_sysreg(far_el1);

	local_daif_inherit(regs);
	do_sp_pc_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el1_pc);

static void notrace el1_undef(struct pt_regs *regs)
{
	local_daif_inherit(regs);
	do_undefinstr(regs);
}
NOKPROBE_SYMBOL(el1_undef);

static void notrace el1_inv(struct pt_regs *regs, unsigned long esr)
{
	local_daif_inherit(regs);
	bad_mode(regs, 0, esr);
}
NOKPROBE_SYMBOL(el1_inv);

static void notrace el1_dbg(struct pt_regs *regs, unsigned long esr)
{
	unsigned long far = read_sysreg(far_el1);

	/*
	 * The CPU masked interrupts, and we are leaving them masked during
	 * do_debug_exception(). Update PMR as if we had called
	 * local_mask_daif().
	 */
	if (system_uses_irq_prio_masking())
		gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);

	do_debug_exception(far, esr, regs);
}
NOKPROBE_SYMBOL(el1_dbg);

asmlinkage void notrace el1_sync_handler(struct pt_regs *regs)
{
	unsigned long esr = read_sysreg(esr_el1);

	switch (ESR_ELx_EC(esr)) {
	case ESR_ELx_EC_DABT_CUR:
	case ESR_ELx_EC_IABT_CUR:
		el1_abort(regs, esr);
		break;
	/*
	 * We don't handle ESR_ELx_EC_SP_ALIGN, since we will have hit a
	 * recursive exception when trying to push the initial pt_regs.
	 */
	case ESR_ELx_EC_PC_ALIGN:
		el1_pc(regs, esr);
		break;
	case ESR_ELx_EC_SYS64:
	case ESR_ELx_EC_UNKNOWN:
		el1_undef(regs);
		break;
	case ESR_ELx_EC_BREAKPT_CUR:
	case ESR_ELx_EC_SOFTSTP_CUR:
	case ESR_ELx_EC_WATCHPT_CUR:
	case ESR_ELx_EC_BRK64:
		el1_dbg(regs, esr);
		break;
	default:
		el1_inv(regs, esr);
	};
}
NOKPROBE_SYMBOL(el1_sync_handler);

static void notrace el0_da(struct pt_regs *regs, unsigned long esr)
{
	unsigned long far = read_sysreg(far_el1);

	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	far = untagged_addr(far);
	do_mem_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_da);

static void notrace el0_ia(struct pt_regs *regs, unsigned long esr)
{
	unsigned long far = read_sysreg(far_el1);

	/*
	 * We've taken an instruction abort from userspace and not yet
	 * re-enabled IRQs. If the address is a kernel address, apply
	 * BP hardening prior to enabling IRQs and pre-emption.
	 */
	if (!is_ttbr0_addr(far))
		arm64_apply_bp_hardening();

	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_mem_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_ia);

static void notrace el0_fpsimd_acc(struct pt_regs *regs, unsigned long esr)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_fpsimd_acc(esr, regs);
}
NOKPROBE_SYMBOL(el0_fpsimd_acc);

static void notrace el0_sve_acc(struct pt_regs *regs, unsigned long esr)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_sve_acc(esr, regs);
}
NOKPROBE_SYMBOL(el0_sve_acc);

static void notrace el0_fpsimd_exc(struct pt_regs *regs, unsigned long esr)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_fpsimd_exc(esr, regs);
}
NOKPROBE_SYMBOL(el0_fpsimd_exc);

static void notrace el0_sys(struct pt_regs *regs, unsigned long esr)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_sysinstr(esr, regs);
}
NOKPROBE_SYMBOL(el0_sys);

static void notrace el0_pc(struct pt_regs *regs, unsigned long esr)
{
	unsigned long far = read_sysreg(far_el1);

	if (!is_ttbr0_addr(instruction_pointer(regs)))
		arm64_apply_bp_hardening();

	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_sp_pc_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_pc);

static void notrace el0_sp(struct pt_regs *regs, unsigned long esr)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX_NOIRQ);
	do_sp_pc_abort(regs->sp, esr, regs);
}
NOKPROBE_SYMBOL(el0_sp);

static void notrace el0_undef(struct pt_regs *regs)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_undefinstr(regs);
}
NOKPROBE_SYMBOL(el0_undef);

static void notrace el0_inv(struct pt_regs *regs, unsigned long esr)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	bad_el0_sync(regs, 0, esr);
}
NOKPROBE_SYMBOL(el0_inv);

static void notrace el0_dbg(struct pt_regs *regs, unsigned long esr)
{
	/* Only watchpoints write FAR_EL1, otherwise its UNKNOWN */
	unsigned long far = read_sysreg(far_el1);

	if (system_uses_irq_prio_masking())
		gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);

	user_exit_irqoff();
	do_debug_exception(far, esr, regs);
	local_daif_restore(DAIF_PROCCTX_NOIRQ);
}
NOKPROBE_SYMBOL(el0_dbg);

static void notrace el0_svc(struct pt_regs *regs)
{
	if (system_uses_irq_prio_masking())
		gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);

	do_el0_svc(regs);
}
NOKPROBE_SYMBOL(el0_svc);

asmlinkage void notrace el0_sync_handler(struct pt_regs *regs)
{
	unsigned long esr = read_sysreg(esr_el1);

	switch (ESR_ELx_EC(esr)) {
	case ESR_ELx_EC_SVC64:
		el0_svc(regs);
		break;
	case ESR_ELx_EC_DABT_LOW:
		el0_da(regs, esr);
		break;
	case ESR_ELx_EC_IABT_LOW:
		el0_ia(regs, esr);
		break;
	case ESR_ELx_EC_FP_ASIMD:
		el0_fpsimd_acc(regs, esr);
		break;
	case ESR_ELx_EC_SVE:
		el0_sve_acc(regs, esr);
		break;
	case ESR_ELx_EC_FP_EXC64:
		el0_fpsimd_exc(regs, esr);
		break;
	case ESR_ELx_EC_SYS64:
	case ESR_ELx_EC_WFx:
		el0_sys(regs, esr);
		break;
	case ESR_ELx_EC_SP_ALIGN:
		el0_sp(regs, esr);
		break;
	case ESR_ELx_EC_PC_ALIGN:
		el0_pc(regs, esr);
		break;
	case ESR_ELx_EC_UNKNOWN:
		el0_undef(regs);
		break;
	case ESR_ELx_EC_BREAKPT_LOW:
	case ESR_ELx_EC_SOFTSTP_LOW:
	case ESR_ELx_EC_WATCHPT_LOW:
	case ESR_ELx_EC_BRK64:
		el0_dbg(regs, esr);
		break;
	default:
		el0_inv(regs, esr);
	}
}
NOKPROBE_SYMBOL(el0_sync_handler);

#ifdef CONFIG_COMPAT
static void notrace el0_cp15(struct pt_regs *regs, unsigned long esr)
{
	user_exit_irqoff();
	local_daif_restore(DAIF_PROCCTX);
	do_cp15instr(esr, regs);
}
NOKPROBE_SYMBOL(el0_cp15);

static void notrace el0_svc_compat(struct pt_regs *regs)
{
	if (system_uses_irq_prio_masking())
		gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);

	do_el0_svc_compat(regs);
}
NOKPROBE_SYMBOL(el0_svc_compat);

asmlinkage void notrace el0_sync_compat_handler(struct pt_regs *regs)
{
	unsigned long esr = read_sysreg(esr_el1);

	switch (ESR_ELx_EC(esr)) {
	case ESR_ELx_EC_SVC32:
		el0_svc_compat(regs);
		break;
	case ESR_ELx_EC_DABT_LOW:
		el0_da(regs, esr);
		break;
	case ESR_ELx_EC_IABT_LOW:
		el0_ia(regs, esr);
		break;
	case ESR_ELx_EC_FP_ASIMD:
		el0_fpsimd_acc(regs, esr);
		break;
	case ESR_ELx_EC_FP_EXC32:
		el0_fpsimd_exc(regs, esr);
		break;
	case ESR_ELx_EC_PC_ALIGN:
		el0_pc(regs, esr);
		break;
	case ESR_ELx_EC_UNKNOWN:
	case ESR_ELx_EC_CP14_MR:
	case ESR_ELx_EC_CP14_LS:
	case ESR_ELx_EC_CP14_64:
		el0_undef(regs);
		break;
	case ESR_ELx_EC_CP15_32:
	case ESR_ELx_EC_CP15_64:
		el0_cp15(regs, esr);
		break;
	case ESR_ELx_EC_BREAKPT_LOW:
	case ESR_ELx_EC_SOFTSTP_LOW:
	case ESR_ELx_EC_WATCHPT_LOW:
	case ESR_ELx_EC_BKPT32:
		el0_dbg(regs, esr);
		break;
	default:
		el0_inv(regs, esr);
	}
}
NOKPROBE_SYMBOL(el0_sync_compat_handler);
#endif /* CONFIG_COMPAT */