[patch V2 38/44] x86/idt: Move regular trap init to tables

Thomas Gleixner
2017-08-25T21:58:21Z

[-- Attachment #1: x86-idt--Move-regular-trap-init-to-tables.patch --]
[-- Type: text/plain, Size: 4433 bytes --]

Initialize the regular traps with a table.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/include/asm/desc.h | 1
arch/x86/kernel/idt.c | 51 ++++++++++++++++++++++++++++++++++++++++++++
arch/x86/kernel/traps.c | 42 +-----------------------------------
3 files changed, 54 insertions(+), 40 deletions(-)

--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -506,6 +506,7 @@ static inline void load_current_idt(void

extern void idt_setup_early_handler(void);
extern void idt_setup_early_traps(void);
+extern void idt_setup_traps(void);

#ifdef CONFIG_X86_64
extern void idt_setup_early_pf(void);
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -60,6 +60,49 @@ static const __initdata struct idt_data
#endif
};

+/*
+ * The default IDT entries which are set up in trap_init() before
+ * cpu_init() is invoked. Interrupt stacks cannot be used at that point and
+ * the traps which use them are reinitialized with IST after cpu_init() has
+ * set up TSS.
+ */
+static const __initdata 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),
+
+#ifdef CONFIG_X86_32
+ TSKG(X86_TRAP_DF, GDT_ENTRY_DOUBLEFAULT_TSS),
+#else
+ INTG(X86_TRAP_DF, double_fault),
+#endif
+ INTG(X86_TRAP_DB, debug),
+ INTG(X86_TRAP_NMI, nmi),
+ INTG(X86_TRAP_BP, int3),
+
+#ifdef CONFIG_X86_MCE
+ INTG(X86_TRAP_MC, &machine_check),
+#endif
+
+ SYSG(X86_TRAP_OF, overflow),
+#if defined(CONFIG_IA32_EMULATION)
+ SYSG(IA32_SYSCALL_VECTOR, entry_INT80_compat),
+#elif defined(CONFIG_X86_32)
+ SYSG(IA32_SYSCALL_VECTOR, entry_INT80_32),
+#endif
+};
+
#ifdef CONFIG_X86_64
/*
* Early traps running on the DEFAULT_STACK because the other interrupt
@@ -153,6 +196,14 @@ void __init idt_setup_early_traps(void)
idt_setup_from_table(idt_table, early_idts, ARRAY_SIZE(early_idts));
}

+/**
+ * idt_setup_traps - Initialize the idt table with default traps
+ */
+void __init idt_setup_traps(void)
+{
+ idt_setup_from_table(idt_table, def_idts, ARRAY_SIZE(def_idts));
+}
+
#ifdef CONFIG_X86_64
/**
* idt_setup_early_pf - Initialize the idt table with early pagefault handler
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -925,46 +925,8 @@ dotraplinkage void do_iret_error(struct

void __init trap_init(void)
{
- int i;
-
- set_intr_gate(X86_TRAP_DE, divide_error);
- set_intr_gate_ist(X86_TRAP_NMI, &nmi, NMI_STACK);
- /* int4 can be called from all */
- set_system_intr_gate(X86_TRAP_OF, &overflow);
- set_intr_gate(X86_TRAP_BR, bounds);
- set_intr_gate(X86_TRAP_UD, invalid_op);
- set_intr_gate(X86_TRAP_NM, device_not_available);
-#ifdef CONFIG_X86_32
- set_task_gate(X86_TRAP_DF, GDT_ENTRY_DOUBLEFAULT_TSS);
-#else
- set_intr_gate_ist(X86_TRAP_DF, &double_fault, DOUBLEFAULT_STACK);
-#endif
- set_intr_gate(X86_TRAP_OLD_MF, coprocessor_segment_overrun);
- set_intr_gate(X86_TRAP_TS, invalid_TSS);
- set_intr_gate(X86_TRAP_NP, segment_not_present);
- set_intr_gate(X86_TRAP_SS, stack_segment);
- set_intr_gate(X86_TRAP_GP, general_protection);
- set_intr_gate(X86_TRAP_SPURIOUS, spurious_interrupt_bug);
- set_intr_gate(X86_TRAP_MF, coprocessor_error);
- set_intr_gate(X86_TRAP_AC, alignment_check);
-#ifdef CONFIG_X86_MCE
- set_intr_gate_ist(X86_TRAP_MC, &machine_check, MCE_STACK);
-#endif
- set_intr_gate(X86_TRAP_XF, simd_coprocessor_error);
-
- /* Reserve all the builtin and the syscall vector: */
- for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
- set_bit(i, used_vectors);
-
-#ifdef CONFIG_IA32_EMULATION
- set_system_intr_gate(IA32_SYSCALL_VECTOR, entry_INT80_compat);
- set_bit(IA32_SYSCALL_VECTOR, used_vectors);
-#endif
-
-#ifdef CONFIG_X86_32
- set_system_intr_gate(IA32_SYSCALL_VECTOR, entry_INT80_32);
- set_bit(IA32_SYSCALL_VECTOR, used_vectors);
-#endif
+ /* Initial trap setup. No IST stacks used. */
+ idt_setup_traps();

/*
* Set the IDT descriptor to a fixed read-only location, so that the