Linux Audio

Check our new training course

Loading...
v4.17
 
  1/*
  2 * Interrupt descriptor table related code
  3 *
  4 * This file is licensed under the GPL V2
  5 */
  6#include <linux/interrupt.h>
  7
 
 
  8#include <asm/traps.h>
  9#include <asm/proto.h>
 10#include <asm/desc.h>
 11
 12struct idt_data {
 13	unsigned int	vector;
 14	unsigned int	segment;
 15	struct idt_bits	bits;
 16	const void	*addr;
 17};
 18
 19#define DPL0		0x0
 20#define DPL3		0x3
 21
 22#define DEFAULT_STACK	0
 23
 24#define G(_vector, _addr, _ist, _type, _dpl, _segment)	\
 25	{						\
 26		.vector		= _vector,		\
 27		.bits.ist	= _ist,			\
 28		.bits.type	= _type,		\
 29		.bits.dpl	= _dpl,			\
 30		.bits.p		= 1,			\
 31		.addr		= _addr,		\
 32		.segment	= _segment,		\
 33	}
 34
 35/* Interrupt gate */
 36#define INTG(_vector, _addr)				\
 37	G(_vector, _addr, DEFAULT_STACK, GATE_INTERRUPT, DPL0, __KERNEL_CS)
 38
 39/* System interrupt gate */
 40#define SYSG(_vector, _addr)				\
 41	G(_vector, _addr, DEFAULT_STACK, GATE_INTERRUPT, DPL3, __KERNEL_CS)
 42
 43/* Interrupt gate with interrupt stack */
 
 
 
 
 44#define ISTG(_vector, _addr, _ist)			\
 45	G(_vector, _addr, _ist, GATE_INTERRUPT, DPL0, __KERNEL_CS)
 46
 47/* System interrupt gate with interrupt stack */
 48#define SISTG(_vector, _addr, _ist)			\
 49	G(_vector, _addr, _ist, GATE_INTERRUPT, DPL3, __KERNEL_CS)
 50
 51/* Task gate */
 52#define TSKG(_vector, _gdt)				\
 53	G(_vector, NULL, DEFAULT_STACK, GATE_TASK, DPL0, _gdt << 3)
 54
 
 
 
 
 55/*
 56 * Early traps running on the DEFAULT_STACK because the other interrupt
 57 * stacks work only after cpu_init().
 58 */
 59static const __initconst struct idt_data early_idts[] = {
 60	INTG(X86_TRAP_DB,		debug),
 61	SYSG(X86_TRAP_BP,		int3),
 
 62#ifdef CONFIG_X86_32
 63	INTG(X86_TRAP_PF,		page_fault),
 
 
 
 
 
 
 64#endif
 65};
 66
 67/*
 68 * The default IDT entries which are set up in trap_init() before
 69 * cpu_init() is invoked. Interrupt stacks cannot be used at that point and
 70 * the traps which use them are reinitialized with IST after cpu_init() has
 71 * set up TSS.
 72 */
 73static const __initconst struct idt_data def_idts[] = {
 74	INTG(X86_TRAP_DE,		divide_error),
 75	INTG(X86_TRAP_NMI,		nmi),
 76	INTG(X86_TRAP_BR,		bounds),
 77	INTG(X86_TRAP_UD,		invalid_op),
 78	INTG(X86_TRAP_NM,		device_not_available),
 79	INTG(X86_TRAP_OLD_MF,		coprocessor_segment_overrun),
 80	INTG(X86_TRAP_TS,		invalid_TSS),
 81	INTG(X86_TRAP_NP,		segment_not_present),
 82	INTG(X86_TRAP_SS,		stack_segment),
 83	INTG(X86_TRAP_GP,		general_protection),
 84	INTG(X86_TRAP_SPURIOUS,		spurious_interrupt_bug),
 85	INTG(X86_TRAP_MF,		coprocessor_error),
 86	INTG(X86_TRAP_AC,		alignment_check),
 87	INTG(X86_TRAP_XF,		simd_coprocessor_error),
 88
 89#ifdef CONFIG_X86_32
 90	TSKG(X86_TRAP_DF,		GDT_ENTRY_DOUBLEFAULT_TSS),
 91#else
 92	INTG(X86_TRAP_DF,		double_fault),
 93#endif
 94	INTG(X86_TRAP_DB,		debug),
 95
 96#ifdef CONFIG_X86_MCE
 97	INTG(X86_TRAP_MC,		&machine_check),
 
 
 
 
 98#endif
 99
100	SYSG(X86_TRAP_OF,		overflow),
 
 
 
 
101#if defined(CONFIG_IA32_EMULATION)
102	SYSG(IA32_SYSCALL_VECTOR,	entry_INT80_compat),
103#elif defined(CONFIG_X86_32)
104	SYSG(IA32_SYSCALL_VECTOR,	entry_INT80_32),
105#endif
106};
107
108/*
109 * The APIC and SMP idt entries
110 */
111static const __initconst struct idt_data apic_idts[] = {
112#ifdef CONFIG_SMP
113	INTG(RESCHEDULE_VECTOR,		reschedule_interrupt),
114	INTG(CALL_FUNCTION_VECTOR,	call_function_interrupt),
115	INTG(CALL_FUNCTION_SINGLE_VECTOR, call_function_single_interrupt),
116	INTG(IRQ_MOVE_CLEANUP_VECTOR,	irq_move_cleanup_interrupt),
117	INTG(REBOOT_VECTOR,		reboot_interrupt),
118#endif
119
120#ifdef CONFIG_X86_THERMAL_VECTOR
121	INTG(THERMAL_APIC_VECTOR,	thermal_interrupt),
122#endif
123
124#ifdef CONFIG_X86_MCE_THRESHOLD
125	INTG(THRESHOLD_APIC_VECTOR,	threshold_interrupt),
126#endif
127
128#ifdef CONFIG_X86_MCE_AMD
129	INTG(DEFERRED_ERROR_VECTOR,	deferred_error_interrupt),
130#endif
131
132#ifdef CONFIG_X86_LOCAL_APIC
133	INTG(LOCAL_TIMER_VECTOR,	apic_timer_interrupt),
134	INTG(X86_PLATFORM_IPI_VECTOR,	x86_platform_ipi),
135# ifdef CONFIG_HAVE_KVM
136	INTG(POSTED_INTR_VECTOR,	kvm_posted_intr_ipi),
137	INTG(POSTED_INTR_WAKEUP_VECTOR, kvm_posted_intr_wakeup_ipi),
138	INTG(POSTED_INTR_NESTED_VECTOR, kvm_posted_intr_nested_ipi),
139# endif
140# ifdef CONFIG_IRQ_WORK
141	INTG(IRQ_WORK_VECTOR,		irq_work_interrupt),
142# endif
143#ifdef CONFIG_X86_UV
144	INTG(UV_BAU_MESSAGE,		uv_bau_message_intr1),
145#endif
146	INTG(SPURIOUS_APIC_VECTOR,	spurious_interrupt),
147	INTG(ERROR_APIC_VECTOR,		error_interrupt),
148#endif
149};
150
151#ifdef CONFIG_X86_64
152/*
153 * Early traps running on the DEFAULT_STACK because the other interrupt
154 * stacks work only after cpu_init().
155 */
156static const __initconst struct idt_data early_pf_idts[] = {
157	INTG(X86_TRAP_PF,		page_fault),
158};
159
160/*
161 * Override for the debug_idt. Same as the default, but with interrupt
162 * stack set to DEFAULT_STACK (0). Required for NMI trap handling.
163 */
164static const __initconst struct idt_data dbg_idts[] = {
165	INTG(X86_TRAP_DB,	debug),
166};
167#endif
168
169/* Must be page-aligned because the real IDT is used in a fixmap. */
170gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss;
171
172struct desc_ptr idt_descr __ro_after_init = {
173	.size		= (IDT_ENTRIES * 2 * sizeof(unsigned long)) - 1,
174	.address	= (unsigned long) idt_table,
175};
176
177#ifdef CONFIG_X86_64
178/* No need to be aligned, but done to keep all IDTs defined the same way. */
179gate_desc debug_idt_table[IDT_ENTRIES] __page_aligned_bss;
180
181/*
182 * The exceptions which use Interrupt stacks. They are setup after
183 * cpu_init() when the TSS has been initialized.
184 */
185static const __initconst struct idt_data ist_idts[] = {
186	ISTG(X86_TRAP_DB,	debug,		DEBUG_STACK),
187	ISTG(X86_TRAP_NMI,	nmi,		NMI_STACK),
188	ISTG(X86_TRAP_DF,	double_fault,	DOUBLEFAULT_STACK),
189#ifdef CONFIG_X86_MCE
190	ISTG(X86_TRAP_MC,	&machine_check,	MCE_STACK),
191#endif
192};
193
194/*
195 * Override for the debug_idt. Same as the default, but with interrupt
196 * stack set to DEFAULT_STACK (0). Required for NMI trap handling.
197 */
198const struct desc_ptr debug_idt_descr = {
199	.size		= IDT_ENTRIES * 16 - 1,
200	.address	= (unsigned long) debug_idt_table,
201};
202#endif
203
204static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d)
205{
206	unsigned long addr = (unsigned long) d->addr;
 
 
207
208	gate->offset_low	= (u16) addr;
209	gate->segment		= (u16) d->segment;
210	gate->bits		= d->bits;
211	gate->offset_middle	= (u16) (addr >> 16);
212#ifdef CONFIG_X86_64
213	gate->offset_high	= (u32) (addr >> 32);
214	gate->reserved		= 0;
215#endif
216}
 
217
218static void
219idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sys)
220{
221	gate_desc desc;
222
223	for (; size > 0; t++, size--) {
224		idt_init_desc(&desc, t);
225		write_idt_entry(idt, t->vector, &desc);
226		if (sys)
227			set_bit(t->vector, system_vectors);
228	}
229}
230
231static void set_intr_gate(unsigned int n, const void *addr)
232{
233	struct idt_data data;
234
235	BUG_ON(n > 0xFF);
236
237	memset(&data, 0, sizeof(data));
238	data.vector	= n;
239	data.addr	= addr;
240	data.segment	= __KERNEL_CS;
241	data.bits.type	= GATE_INTERRUPT;
242	data.bits.p	= 1;
243
244	idt_setup_from_table(idt_table, &data, 1, false);
245}
246
247/**
248 * idt_setup_early_traps - Initialize the idt table with early traps
249 *
250 * On X8664 these traps do not use interrupt stacks as they can't work
251 * before cpu_init() is invoked and sets up TSS. The IST variants are
252 * installed after that.
253 */
254void __init idt_setup_early_traps(void)
255{
256	idt_setup_from_table(idt_table, early_idts, ARRAY_SIZE(early_idts),
257			     true);
258	load_idt(&idt_descr);
259}
260
261/**
262 * idt_setup_traps - Initialize the idt table with default traps
263 */
264void __init idt_setup_traps(void)
265{
266	idt_setup_from_table(idt_table, def_idts, ARRAY_SIZE(def_idts), true);
267}
268
269#ifdef CONFIG_X86_64
 
 
 
 
 
 
 
 
270/**
271 * idt_setup_early_pf - Initialize the idt table with early pagefault handler
272 *
273 * On X8664 this does not use interrupt stacks as they can't work before
274 * cpu_init() is invoked and sets up TSS. The IST variant is installed
275 * after that.
276 *
277 * FIXME: Why is 32bit and 64bit installing the PF handler at different
278 * places in the early setup code?
 
 
279 */
280void __init idt_setup_early_pf(void)
281{
282	idt_setup_from_table(idt_table, early_pf_idts,
283			     ARRAY_SIZE(early_pf_idts), true);
284}
 
285
286/**
287 * idt_setup_ist_traps - Initialize the idt table with traps using IST
288 */
289void __init idt_setup_ist_traps(void)
290{
291	idt_setup_from_table(idt_table, ist_idts, ARRAY_SIZE(ist_idts), true);
292}
293
294/**
295 * idt_setup_debugidt_traps - Initialize the debug idt table with debug traps
296 */
297void __init idt_setup_debugidt_traps(void)
298{
299	memcpy(&debug_idt_table, &idt_table, IDT_ENTRIES * 16);
300
301	idt_setup_from_table(debug_idt_table, dbg_idts, ARRAY_SIZE(dbg_idts), false);
 
 
 
 
 
 
302}
303#endif
304
305/**
306 * idt_setup_apic_and_irq_gates - Setup APIC/SMP and normal interrupt gates
307 */
308void __init idt_setup_apic_and_irq_gates(void)
309{
310	int i = FIRST_EXTERNAL_VECTOR;
311	void *entry;
312
313	idt_setup_from_table(idt_table, apic_idts, ARRAY_SIZE(apic_idts), true);
314
315	for_each_clear_bit_from(i, system_vectors, FIRST_SYSTEM_VECTOR) {
316		entry = irq_entries_start + 8 * (i - FIRST_EXTERNAL_VECTOR);
317		set_intr_gate(i, entry);
318	}
319
320	for_each_clear_bit_from(i, system_vectors, NR_VECTORS) {
321#ifdef CONFIG_X86_LOCAL_APIC
322		set_bit(i, system_vectors);
323		set_intr_gate(i, spurious_interrupt);
324#else
325		entry = irq_entries_start + 8 * (i - FIRST_EXTERNAL_VECTOR);
 
 
 
326		set_intr_gate(i, entry);
327#endif
328	}
 
 
 
 
 
 
 
 
 
329}
330
331/**
332 * idt_setup_early_handler - Initializes the idt table with early handlers
333 */
334void __init idt_setup_early_handler(void)
335{
336	int i;
337
338	for (i = 0; i < NUM_EXCEPTION_VECTORS; i++)
339		set_intr_gate(i, early_idt_handler_array[i]);
340#ifdef CONFIG_X86_32
341	for ( ; i < NR_VECTORS; i++)
342		set_intr_gate(i, early_ignore_irq);
343#endif
344	load_idt(&idt_descr);
345}
346
347/**
348 * idt_invalidate - Invalidate interrupt descriptor table
349 * @addr:	The virtual address of the 'invalid' IDT
350 */
351void idt_invalidate(void *addr)
352{
353	struct desc_ptr idt = { .address = (unsigned long) addr, .size = 0 };
354
355	load_idt(&idt);
356}
357
358void __init update_intr_gate(unsigned int n, const void *addr)
359{
360	if (WARN_ON_ONCE(!test_bit(n, system_vectors)))
361		return;
362	set_intr_gate(n, addr);
363}
364
365void alloc_intr_gate(unsigned int n, const void *addr)
366{
367	BUG_ON(n < FIRST_SYSTEM_VECTOR);
368	if (!test_and_set_bit(n, system_vectors))
369		set_intr_gate(n, addr);
370}
v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Interrupt descriptor table related code
 
 
  4 */
  5#include <linux/interrupt.h>
  6
  7#include <asm/cpu_entry_area.h>
  8#include <asm/set_memory.h>
  9#include <asm/traps.h>
 10#include <asm/proto.h>
 11#include <asm/desc.h>
 12#include <asm/hw_irq.h>
 13#include <asm/idtentry.h>
 
 
 
 
 
 14
 15#define DPL0		0x0
 16#define DPL3		0x3
 17
 18#define DEFAULT_STACK	0
 19
 20#define G(_vector, _addr, _ist, _type, _dpl, _segment)	\
 21	{						\
 22		.vector		= _vector,		\
 23		.bits.ist	= _ist,			\
 24		.bits.type	= _type,		\
 25		.bits.dpl	= _dpl,			\
 26		.bits.p		= 1,			\
 27		.addr		= _addr,		\
 28		.segment	= _segment,		\
 29	}
 30
 31/* Interrupt gate */
 32#define INTG(_vector, _addr)				\
 33	G(_vector, _addr, DEFAULT_STACK, GATE_INTERRUPT, DPL0, __KERNEL_CS)
 34
 35/* System interrupt gate */
 36#define SYSG(_vector, _addr)				\
 37	G(_vector, _addr, DEFAULT_STACK, GATE_INTERRUPT, DPL3, __KERNEL_CS)
 38
 39#ifdef CONFIG_X86_64
 40/*
 41 * Interrupt gate with interrupt stack. The _ist index is the index in
 42 * the tss.ist[] array, but for the descriptor it needs to start at 1.
 43 */
 44#define ISTG(_vector, _addr, _ist)			\
 45	G(_vector, _addr, _ist + 1, GATE_INTERRUPT, DPL0, __KERNEL_CS)
 46#else
 47#define ISTG(_vector, _addr, _ist)	INTG(_vector, _addr)
 48#endif
 
 49
 50/* Task gate */
 51#define TSKG(_vector, _gdt)				\
 52	G(_vector, NULL, DEFAULT_STACK, GATE_TASK, DPL0, _gdt << 3)
 53
 54#define IDT_TABLE_SIZE		(IDT_ENTRIES * sizeof(gate_desc))
 55
 56static bool idt_setup_done __initdata;
 57
 58/*
 59 * Early traps running on the DEFAULT_STACK because the other interrupt
 60 * stacks work only after cpu_init().
 61 */
 62static const __initconst struct idt_data early_idts[] = {
 63	INTG(X86_TRAP_DB,		asm_exc_debug),
 64	SYSG(X86_TRAP_BP,		asm_exc_int3),
 65
 66#ifdef CONFIG_X86_32
 67	/*
 68	 * Not possible on 64-bit. See idt_setup_early_pf() for details.
 69	 */
 70	INTG(X86_TRAP_PF,		asm_exc_page_fault),
 71#endif
 72#ifdef CONFIG_INTEL_TDX_GUEST
 73	INTG(X86_TRAP_VE,		asm_exc_virtualization_exception),
 74#endif
 75};
 76
 77/*
 78 * The default IDT entries which are set up in trap_init() before
 79 * cpu_init() is invoked. Interrupt stacks cannot be used at that point and
 80 * the traps which use them are reinitialized with IST after cpu_init() has
 81 * set up TSS.
 82 */
 83static const __initconst struct idt_data def_idts[] = {
 84	INTG(X86_TRAP_DE,		asm_exc_divide_error),
 85	ISTG(X86_TRAP_NMI,		asm_exc_nmi, IST_INDEX_NMI),
 86	INTG(X86_TRAP_BR,		asm_exc_bounds),
 87	INTG(X86_TRAP_UD,		asm_exc_invalid_op),
 88	INTG(X86_TRAP_NM,		asm_exc_device_not_available),
 89	INTG(X86_TRAP_OLD_MF,		asm_exc_coproc_segment_overrun),
 90	INTG(X86_TRAP_TS,		asm_exc_invalid_tss),
 91	INTG(X86_TRAP_NP,		asm_exc_segment_not_present),
 92	INTG(X86_TRAP_SS,		asm_exc_stack_segment),
 93	INTG(X86_TRAP_GP,		asm_exc_general_protection),
 94	INTG(X86_TRAP_SPURIOUS,		asm_exc_spurious_interrupt_bug),
 95	INTG(X86_TRAP_MF,		asm_exc_coprocessor_error),
 96	INTG(X86_TRAP_AC,		asm_exc_alignment_check),
 97	INTG(X86_TRAP_XF,		asm_exc_simd_coprocessor_error),
 98
 99#ifdef CONFIG_X86_32
100	TSKG(X86_TRAP_DF,		GDT_ENTRY_DOUBLEFAULT_TSS),
101#else
102	ISTG(X86_TRAP_DF,		asm_exc_double_fault, IST_INDEX_DF),
103#endif
104	ISTG(X86_TRAP_DB,		asm_exc_debug, IST_INDEX_DB),
105
106#ifdef CONFIG_X86_MCE
107	ISTG(X86_TRAP_MC,		asm_exc_machine_check, IST_INDEX_MCE),
108#endif
109
110#ifdef CONFIG_X86_KERNEL_IBT
111	INTG(X86_TRAP_CP,		asm_exc_control_protection),
112#endif
113
114#ifdef CONFIG_AMD_MEM_ENCRYPT
115	ISTG(X86_TRAP_VC,		asm_exc_vmm_communication, IST_INDEX_VC),
116#endif
117
118	SYSG(X86_TRAP_OF,		asm_exc_overflow),
119#if defined(CONFIG_IA32_EMULATION)
120	SYSG(IA32_SYSCALL_VECTOR,	entry_INT80_compat),
121#elif defined(CONFIG_X86_32)
122	SYSG(IA32_SYSCALL_VECTOR,	entry_INT80_32),
123#endif
124};
125
126/*
127 * The APIC and SMP idt entries
128 */
129static const __initconst struct idt_data apic_idts[] = {
130#ifdef CONFIG_SMP
131	INTG(RESCHEDULE_VECTOR,			asm_sysvec_reschedule_ipi),
132	INTG(CALL_FUNCTION_VECTOR,		asm_sysvec_call_function),
133	INTG(CALL_FUNCTION_SINGLE_VECTOR,	asm_sysvec_call_function_single),
134	INTG(IRQ_MOVE_CLEANUP_VECTOR,		asm_sysvec_irq_move_cleanup),
135	INTG(REBOOT_VECTOR,			asm_sysvec_reboot),
136#endif
137
138#ifdef CONFIG_X86_THERMAL_VECTOR
139	INTG(THERMAL_APIC_VECTOR,		asm_sysvec_thermal),
140#endif
141
142#ifdef CONFIG_X86_MCE_THRESHOLD
143	INTG(THRESHOLD_APIC_VECTOR,		asm_sysvec_threshold),
144#endif
145
146#ifdef CONFIG_X86_MCE_AMD
147	INTG(DEFERRED_ERROR_VECTOR,		asm_sysvec_deferred_error),
148#endif
149
150#ifdef CONFIG_X86_LOCAL_APIC
151	INTG(LOCAL_TIMER_VECTOR,		asm_sysvec_apic_timer_interrupt),
152	INTG(X86_PLATFORM_IPI_VECTOR,		asm_sysvec_x86_platform_ipi),
153# ifdef CONFIG_HAVE_KVM
154	INTG(POSTED_INTR_VECTOR,		asm_sysvec_kvm_posted_intr_ipi),
155	INTG(POSTED_INTR_WAKEUP_VECTOR,		asm_sysvec_kvm_posted_intr_wakeup_ipi),
156	INTG(POSTED_INTR_NESTED_VECTOR,		asm_sysvec_kvm_posted_intr_nested_ipi),
157# endif
158# ifdef CONFIG_IRQ_WORK
159	INTG(IRQ_WORK_VECTOR,			asm_sysvec_irq_work),
160# endif
161	INTG(SPURIOUS_APIC_VECTOR,		asm_sysvec_spurious_apic_interrupt),
162	INTG(ERROR_APIC_VECTOR,			asm_sysvec_error_interrupt),
 
 
 
163#endif
164};
165
166/* Must be page-aligned because the real IDT is used in the cpu entry area */
167static gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
168
169static struct desc_ptr idt_descr __ro_after_init = {
170	.size		= IDT_TABLE_SIZE - 1,
171	.address	= (unsigned long) idt_table,
172};
173
174void load_current_idt(void)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
175{
176	lockdep_assert_irqs_disabled();
177	load_idt(&idt_descr);
178}
179
180#ifdef CONFIG_X86_F00F_BUG
181bool idt_is_f00f_address(unsigned long address)
182{
183	return ((address - idt_descr.address) >> 3) == 6;
 
 
 
 
184}
185#endif
186
187static __init void
188idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sys)
189{
190	gate_desc desc;
191
192	for (; size > 0; t++, size--) {
193		idt_init_desc(&desc, t);
194		write_idt_entry(idt, t->vector, &desc);
195		if (sys)
196			set_bit(t->vector, system_vectors);
197	}
198}
199
200static __init void set_intr_gate(unsigned int n, const void *addr)
201{
202	struct idt_data data;
203
204	init_idt_data(&data, n, addr);
 
 
 
 
 
 
 
205
206	idt_setup_from_table(idt_table, &data, 1, false);
207}
208
209/**
210 * idt_setup_early_traps - Initialize the idt table with early traps
211 *
212 * On X8664 these traps do not use interrupt stacks as they can't work
213 * before cpu_init() is invoked and sets up TSS. The IST variants are
214 * installed after that.
215 */
216void __init idt_setup_early_traps(void)
217{
218	idt_setup_from_table(idt_table, early_idts, ARRAY_SIZE(early_idts),
219			     true);
220	load_idt(&idt_descr);
221}
222
223/**
224 * idt_setup_traps - Initialize the idt table with default traps
225 */
226void __init idt_setup_traps(void)
227{
228	idt_setup_from_table(idt_table, def_idts, ARRAY_SIZE(def_idts), true);
229}
230
231#ifdef CONFIG_X86_64
232/*
233 * Early traps running on the DEFAULT_STACK because the other interrupt
234 * stacks work only after cpu_init().
235 */
236static const __initconst struct idt_data early_pf_idts[] = {
237	INTG(X86_TRAP_PF,		asm_exc_page_fault),
238};
239
240/**
241 * idt_setup_early_pf - Initialize the idt table with early pagefault handler
242 *
243 * On X8664 this does not use interrupt stacks as they can't work before
244 * cpu_init() is invoked and sets up TSS. The IST variant is installed
245 * after that.
246 *
247 * Note, that X86_64 cannot install the real #PF handler in
248 * idt_setup_early_traps() because the memory initialization needs the #PF
249 * handler from the early_idt_handler_array to initialize the early page
250 * tables.
251 */
252void __init idt_setup_early_pf(void)
253{
254	idt_setup_from_table(idt_table, early_pf_idts,
255			     ARRAY_SIZE(early_pf_idts), true);
256}
257#endif
258
259static void __init idt_map_in_cea(void)
 
 
 
 
 
 
 
 
 
 
 
260{
261	/*
262	 * Set the IDT descriptor to a fixed read-only location in the cpu
263	 * entry area, so that the "sidt" instruction will not leak the
264	 * location of the kernel, and to defend the IDT against arbitrary
265	 * memory write vulnerabilities.
266	 */
267	cea_set_pte(CPU_ENTRY_AREA_RO_IDT_VADDR, __pa_symbol(idt_table),
268		    PAGE_KERNEL_RO);
269	idt_descr.address = CPU_ENTRY_AREA_RO_IDT;
270}
 
271
272/**
273 * idt_setup_apic_and_irq_gates - Setup APIC/SMP and normal interrupt gates
274 */
275void __init idt_setup_apic_and_irq_gates(void)
276{
277	int i = FIRST_EXTERNAL_VECTOR;
278	void *entry;
279
280	idt_setup_from_table(idt_table, apic_idts, ARRAY_SIZE(apic_idts), true);
281
282	for_each_clear_bit_from(i, system_vectors, FIRST_SYSTEM_VECTOR) {
283		entry = irq_entries_start + IDT_ALIGN * (i - FIRST_EXTERNAL_VECTOR);
284		set_intr_gate(i, entry);
285	}
286
 
287#ifdef CONFIG_X86_LOCAL_APIC
288	for_each_clear_bit_from(i, system_vectors, NR_VECTORS) {
289		/*
290		 * Don't set the non assigned system vectors in the
291		 * system_vectors bitmap. Otherwise they show up in
292		 * /proc/interrupts.
293		 */
294		entry = spurious_entries_start + IDT_ALIGN * (i - FIRST_SYSTEM_VECTOR);
295		set_intr_gate(i, entry);
 
296	}
297#endif
298	/* Map IDT into CPU entry area and reload it. */
299	idt_map_in_cea();
300	load_idt(&idt_descr);
301
302	/* Make the IDT table read only */
303	set_memory_ro((unsigned long)&idt_table, 1);
304
305	idt_setup_done = true;
306}
307
308/**
309 * idt_setup_early_handler - Initializes the idt table with early handlers
310 */
311void __init idt_setup_early_handler(void)
312{
313	int i;
314
315	for (i = 0; i < NUM_EXCEPTION_VECTORS; i++)
316		set_intr_gate(i, early_idt_handler_array[i]);
317#ifdef CONFIG_X86_32
318	for ( ; i < NR_VECTORS; i++)
319		set_intr_gate(i, early_ignore_irq);
320#endif
321	load_idt(&idt_descr);
322}
323
324/**
325 * idt_invalidate - Invalidate interrupt descriptor table
 
326 */
327void idt_invalidate(void)
328{
329	static const struct desc_ptr idt = { .address = 0, .size = 0 };
330
331	load_idt(&idt);
332}
333
334void __init alloc_intr_gate(unsigned int n, const void *addr)
335{
336	if (WARN_ON(n < FIRST_SYSTEM_VECTOR))
337		return;
 
 
338
339	if (WARN_ON(idt_setup_done))
340		return;
341
342	if (!WARN_ON(test_and_set_bit(n, system_vectors)))
343		set_intr_gate(n, addr);
344}