diff options
Diffstat (limited to 'arch/x86/kernel/idt.c')
| -rw-r--r-- | arch/x86/kernel/idt.c | 226 |
1 files changed, 120 insertions, 106 deletions
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index 87ef69a72c52..0db21206f2f3 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -4,6 +4,8 @@ */ #include <linux/interrupt.h> +#include <asm/cpu_entry_area.h> +#include <asm/set_memory.h> #include <asm/traps.h> #include <asm/proto.h> #include <asm/desc.h> @@ -51,15 +53,23 @@ struct idt_data { #define TSKG(_vector, _gdt) \ G(_vector, NULL, DEFAULT_STACK, GATE_TASK, DPL0, _gdt << 3) +#define IDT_TABLE_SIZE (IDT_ENTRIES * sizeof(gate_desc)) + +static bool idt_setup_done __initdata; + /* * Early traps running on the DEFAULT_STACK because the other interrupt * stacks work only after cpu_init(). */ static const __initconst struct idt_data early_idts[] = { - INTG(X86_TRAP_DB, debug), - SYSG(X86_TRAP_BP, int3), + INTG(X86_TRAP_DB, asm_exc_debug), + SYSG(X86_TRAP_BP, asm_exc_int3), + #ifdef CONFIG_X86_32 - INTG(X86_TRAP_PF, page_fault), + /* + * Not possible on 64-bit. See idt_setup_early_pf() for details. + */ + INTG(X86_TRAP_PF, asm_exc_page_fault), #endif }; @@ -70,33 +80,33 @@ static const __initconst struct idt_data early_idts[] = { * set up TSS. */ static const __initconst struct idt_data def_idts[] = { - INTG(X86_TRAP_DE, divide_error), - INTG(X86_TRAP_NMI, nmi), - INTG(X86_TRAP_BR, bounds), - INTG(X86_TRAP_UD, invalid_op), - INTG(X86_TRAP_NM, device_not_available), - INTG(X86_TRAP_OLD_MF, coprocessor_segment_overrun), - INTG(X86_TRAP_TS, invalid_TSS), - INTG(X86_TRAP_NP, segment_not_present), - INTG(X86_TRAP_SS, stack_segment), - INTG(X86_TRAP_GP, general_protection), - INTG(X86_TRAP_SPURIOUS, spurious_interrupt_bug), - INTG(X86_TRAP_MF, coprocessor_error), - INTG(X86_TRAP_AC, alignment_check), - INTG(X86_TRAP_XF, simd_coprocessor_error), + INTG(X86_TRAP_DE, asm_exc_divide_error), + INTG(X86_TRAP_NMI, asm_exc_nmi), + INTG(X86_TRAP_BR, asm_exc_bounds), + INTG(X86_TRAP_UD, asm_exc_invalid_op), + INTG(X86_TRAP_NM, asm_exc_device_not_available), + INTG(X86_TRAP_OLD_MF, asm_exc_coproc_segment_overrun), + INTG(X86_TRAP_TS, asm_exc_invalid_tss), + INTG(X86_TRAP_NP, asm_exc_segment_not_present), + INTG(X86_TRAP_SS, asm_exc_stack_segment), + INTG(X86_TRAP_GP, asm_exc_general_protection), + INTG(X86_TRAP_SPURIOUS, asm_exc_spurious_interrupt_bug), + INTG(X86_TRAP_MF, asm_exc_coprocessor_error), + INTG(X86_TRAP_AC, asm_exc_alignment_check), + INTG(X86_TRAP_XF, asm_exc_simd_coprocessor_error), #ifdef CONFIG_X86_32 TSKG(X86_TRAP_DF, GDT_ENTRY_DOUBLEFAULT_TSS), #else - INTG(X86_TRAP_DF, double_fault), + INTG(X86_TRAP_DF, asm_exc_double_fault), #endif - INTG(X86_TRAP_DB, debug), + INTG(X86_TRAP_DB, asm_exc_debug), #ifdef CONFIG_X86_MCE - INTG(X86_TRAP_MC, &machine_check), + INTG(X86_TRAP_MC, asm_exc_machine_check), #endif - SYSG(X86_TRAP_OF, overflow), + SYSG(X86_TRAP_OF, asm_exc_overflow), #if defined(CONFIG_IA32_EMULATION) SYSG(IA32_SYSCALL_VECTOR, entry_INT80_compat), #elif defined(CONFIG_X86_32) @@ -109,95 +119,63 @@ static const __initconst struct idt_data def_idts[] = { */ static const __initconst struct idt_data apic_idts[] = { #ifdef CONFIG_SMP - INTG(RESCHEDULE_VECTOR, reschedule_interrupt), - INTG(CALL_FUNCTION_VECTOR, call_function_interrupt), - INTG(CALL_FUNCTION_SINGLE_VECTOR, call_function_single_interrupt), - INTG(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt), - INTG(REBOOT_VECTOR, reboot_interrupt), + INTG(RESCHEDULE_VECTOR, asm_sysvec_reschedule_ipi), + INTG(CALL_FUNCTION_VECTOR, asm_sysvec_call_function), + INTG(CALL_FUNCTION_SINGLE_VECTOR, asm_sysvec_call_function_single), + INTG(IRQ_MOVE_CLEANUP_VECTOR, asm_sysvec_irq_move_cleanup), + INTG(REBOOT_VECTOR, asm_sysvec_reboot), #endif #ifdef CONFIG_X86_THERMAL_VECTOR - INTG(THERMAL_APIC_VECTOR, thermal_interrupt), + INTG(THERMAL_APIC_VECTOR, asm_sysvec_thermal), #endif #ifdef CONFIG_X86_MCE_THRESHOLD - INTG(THRESHOLD_APIC_VECTOR, threshold_interrupt), + INTG(THRESHOLD_APIC_VECTOR, asm_sysvec_threshold), #endif #ifdef CONFIG_X86_MCE_AMD - INTG(DEFERRED_ERROR_VECTOR, deferred_error_interrupt), + INTG(DEFERRED_ERROR_VECTOR, asm_sysvec_deferred_error), #endif #ifdef CONFIG_X86_LOCAL_APIC - INTG(LOCAL_TIMER_VECTOR, apic_timer_interrupt), - INTG(X86_PLATFORM_IPI_VECTOR, x86_platform_ipi), + INTG(LOCAL_TIMER_VECTOR, asm_sysvec_apic_timer_interrupt), + INTG(X86_PLATFORM_IPI_VECTOR, asm_sysvec_x86_platform_ipi), # ifdef CONFIG_HAVE_KVM - INTG(POSTED_INTR_VECTOR, kvm_posted_intr_ipi), - INTG(POSTED_INTR_WAKEUP_VECTOR, kvm_posted_intr_wakeup_ipi), - INTG(POSTED_INTR_NESTED_VECTOR, kvm_posted_intr_nested_ipi), + INTG(POSTED_INTR_VECTOR, asm_sysvec_kvm_posted_intr_ipi), + INTG(POSTED_INTR_WAKEUP_VECTOR, asm_sysvec_kvm_posted_intr_wakeup_ipi), + INTG(POSTED_INTR_NESTED_VECTOR, asm_sysvec_kvm_posted_intr_nested_ipi), # endif # ifdef CONFIG_IRQ_WORK - INTG(IRQ_WORK_VECTOR, irq_work_interrupt), + INTG(IRQ_WORK_VECTOR, asm_sysvec_irq_work), # endif -#ifdef CONFIG_X86_UV - INTG(UV_BAU_MESSAGE, uv_bau_message_intr1), -#endif - INTG(SPURIOUS_APIC_VECTOR, spurious_interrupt), - INTG(ERROR_APIC_VECTOR, error_interrupt), +# ifdef CONFIG_X86_UV + INTG(UV_BAU_MESSAGE, asm_sysvec_uv_bau_message), +# endif + INTG(SPURIOUS_APIC_VECTOR, asm_sysvec_spurious_apic_interrupt), + INTG(ERROR_APIC_VECTOR, asm_sysvec_error_interrupt), #endif }; -#ifdef CONFIG_X86_64 -/* - * Early traps running on the DEFAULT_STACK because the other interrupt - * stacks work only after cpu_init(). - */ -static const __initconst struct idt_data early_pf_idts[] = { - INTG(X86_TRAP_PF, page_fault), -}; - -/* - * Override for the debug_idt. Same as the default, but with interrupt - * stack set to DEFAULT_STACK (0). Required for NMI trap handling. - */ -static const __initconst struct idt_data dbg_idts[] = { - INTG(X86_TRAP_DB, debug), -}; -#endif - -/* Must be page-aligned because the real IDT is used in a fixmap. */ -gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss; +/* Must be page-aligned because the real IDT is used in the cpu entry area */ +static gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss; struct desc_ptr idt_descr __ro_after_init = { - .size = (IDT_ENTRIES * 2 * sizeof(unsigned long)) - 1, + .size = IDT_TABLE_SIZE - 1, .address = (unsigned long) idt_table, }; -#ifdef CONFIG_X86_64 -/* No need to be aligned, but done to keep all IDTs defined the same way. */ -gate_desc debug_idt_table[IDT_ENTRIES] __page_aligned_bss; - -/* - * The exceptions which use Interrupt stacks. They are setup after - * cpu_init() when the TSS has been initialized. - */ -static const __initconst struct idt_data ist_idts[] = { - ISTG(X86_TRAP_DB, debug, IST_INDEX_DB), - ISTG(X86_TRAP_NMI, nmi, IST_INDEX_NMI), - ISTG(X86_TRAP_DF, double_fault, IST_INDEX_DF), -#ifdef CONFIG_X86_MCE - ISTG(X86_TRAP_MC, &machine_check, IST_INDEX_MCE), -#endif -}; +void load_current_idt(void) +{ + lockdep_assert_irqs_disabled(); + load_idt(&idt_descr); +} -/* - * Override for the debug_idt. Same as the default, but with interrupt - * stack set to DEFAULT_STACK (0). Required for NMI trap handling. - */ -const struct desc_ptr debug_idt_descr = { - .size = IDT_ENTRIES * 16 - 1, - .address = (unsigned long) debug_idt_table, -}; +#ifdef CONFIG_X86_F00F_BUG +bool idt_is_f00f_address(unsigned long address) +{ + return ((address - idt_descr.address) >> 3) == 6; +} #endif static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d) @@ -214,7 +192,7 @@ static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d) #endif } -static void +static __init void idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sys) { gate_desc desc; @@ -227,7 +205,7 @@ idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sy } } -static void set_intr_gate(unsigned int n, const void *addr) +static __init void set_intr_gate(unsigned int n, const void *addr) { struct idt_data data; @@ -266,6 +244,27 @@ void __init idt_setup_traps(void) } #ifdef CONFIG_X86_64 +/* + * Early traps running on the DEFAULT_STACK because the other interrupt + * stacks work only after cpu_init(). + */ +static const __initconst struct idt_data early_pf_idts[] = { + INTG(X86_TRAP_PF, asm_exc_page_fault), +}; + +/* + * The exceptions which use Interrupt stacks. They are setup after + * cpu_init() when the TSS has been initialized. + */ +static const __initconst struct idt_data ist_idts[] = { + ISTG(X86_TRAP_DB, asm_exc_debug, IST_INDEX_DB), + ISTG(X86_TRAP_NMI, asm_exc_nmi, IST_INDEX_NMI), + ISTG(X86_TRAP_DF, asm_exc_double_fault, IST_INDEX_DF), +#ifdef CONFIG_X86_MCE + ISTG(X86_TRAP_MC, asm_exc_machine_check, IST_INDEX_MCE), +#endif +}; + /** * idt_setup_early_pf - Initialize the idt table with early pagefault handler * @@ -273,8 +272,10 @@ void __init idt_setup_traps(void) * cpu_init() is invoked and sets up TSS. The IST variant is installed * after that. * - * FIXME: Why is 32bit and 64bit installing the PF handler at different - * places in the early setup code? + * Note, that X86_64 cannot install the real #PF handler in + * idt_setup_early_traps() because the memory intialization needs the #PF + * handler from the early_idt_handler_array to initialize the early page + * tables. */ void __init idt_setup_early_pf(void) { @@ -289,17 +290,20 @@ void __init idt_setup_ist_traps(void) { idt_setup_from_table(idt_table, ist_idts, ARRAY_SIZE(ist_idts), true); } +#endif -/** - * idt_setup_debugidt_traps - Initialize the debug idt table with debug traps - */ -void __init idt_setup_debugidt_traps(void) +static void __init idt_map_in_cea(void) { - memcpy(&debug_idt_table, &idt_table, IDT_ENTRIES * 16); - - idt_setup_from_table(debug_idt_table, dbg_idts, ARRAY_SIZE(dbg_idts), false); + /* + * Set the IDT descriptor to a fixed read-only location in the cpu + * entry area, so that the "sidt" instruction will not leak the + * location of the kernel, and to defend the IDT against arbitrary + * memory write vulnerabilities. + */ + cea_set_pte(CPU_ENTRY_AREA_RO_IDT_VADDR, __pa_symbol(idt_table), + PAGE_KERNEL_RO); + idt_descr.address = CPU_ENTRY_AREA_RO_IDT; } -#endif /** * idt_setup_apic_and_irq_gates - Setup APIC/SMP and normal interrupt gates @@ -318,11 +322,23 @@ void __init idt_setup_apic_and_irq_gates(void) #ifdef CONFIG_X86_LOCAL_APIC for_each_clear_bit_from(i, system_vectors, NR_VECTORS) { - set_bit(i, system_vectors); + /* + * Don't set the non assigned system vectors in the + * system_vectors bitmap. Otherwise they show up in + * /proc/interrupts. + */ entry = spurious_entries_start + 8 * (i - FIRST_SYSTEM_VECTOR); set_intr_gate(i, entry); } #endif + /* Map IDT into CPU entry area and reload it. */ + idt_map_in_cea(); + load_idt(&idt_descr); + + /* Make the IDT table read only */ + set_memory_ro((unsigned long)&idt_table, 1); + + idt_setup_done = true; } /** @@ -352,16 +368,14 @@ void idt_invalidate(void *addr) load_idt(&idt); } -void __init update_intr_gate(unsigned int n, const void *addr) +void __init alloc_intr_gate(unsigned int n, const void *addr) { - if (WARN_ON_ONCE(!test_bit(n, system_vectors))) + if (WARN_ON(n < FIRST_SYSTEM_VECTOR)) return; - set_intr_gate(n, addr); -} -void alloc_intr_gate(unsigned int n, const void *addr) -{ - BUG_ON(n < FIRST_SYSTEM_VECTOR); - if (!test_and_set_bit(n, system_vectors)) + if (WARN_ON(idt_setup_done)) + return; + + if (!WARN_ON(test_and_set_bit(n, system_vectors))) set_intr_gate(n, addr); } |