x86/idt: Use proper constants for table size

Use the actual struct size to calculate the IDT table size instead of
hardcoded values.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200528145522.898591501@linutronix.de

diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 5ef82fc..b6e1a87 100644 (file)
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -51,6 +51,7 @@ 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;
 
@@ -168,7 +169,7 @@ static const __initconst struct idt_data early_pf_idts[] = {
 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,
 };