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Subject[patch 4/5] x86/idt: Cleanup trap_init()
No point in having all the IDT cruft in trap_init(). Move it into the IDT
code, get rid of the extra global function and fixup the comments.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/include/asm/desc.h | 2 --
arch/x86/kernel/idt.c | 26 +++++++++++++++++++-------
arch/x86/kernel/traps.c | 11 -----------
3 files changed, 19 insertions(+), 20 deletions(-)

--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -438,11 +438,9 @@ extern void idt_setup_apic_and_irq_gates
#ifdef CONFIG_X86_64
extern void idt_setup_early_pf(void);
extern void idt_setup_ist_traps(void);
-extern void idt_setup_debugidt_traps(void);
#else
static inline void idt_setup_early_pf(void) { }
static inline void idt_setup_ist_traps(void) { }
-static inline void idt_setup_debugidt_traps(void) { }
#endif

extern void idt_invalidate(void *addr);
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -4,6 +4,7 @@
*/
#include <linux/interrupt.h>

+#include <asm/cpu_entry_area.h>
#include <asm/traps.h>
#include <asm/proto.h>
#include <asm/desc.h>
@@ -299,20 +300,27 @@ void __init idt_setup_early_pf(void)
void __init idt_setup_ist_traps(void)
{
idt_setup_from_table(idt_table, ist_idts, ARRAY_SIZE(ist_idts), true);
-}

-/**
- * idt_setup_debugidt_traps - Initialize the debug idt table with debug traps
- */
-void __init idt_setup_debugidt_traps(void)
-{
+ /* All traps set up: Initialize the debug IDT table. */
memcpy(&debug_idt_table, &idt_table, IDT_DEBUG_TABLE_SIZE);
-
idt_setup_from_table(debug_idt_table, dbg_idts, ARRAY_SIZE(dbg_idts),
false);
}
#endif

+static void idt_map_in_cea(void)
+{
+ /*
+ * 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;
+}
+
/**
* idt_setup_apic_and_irq_gates - Setup APIC/SMP and normal interrupt gates
*/
@@ -339,6 +347,10 @@ void __init idt_setup_apic_and_irq_gates
set_intr_gate(i, entry);
}
#endif
+ /* Map IDT into CPU entry area and reload it. */
+ idt_map_in_cea();
+ load_current_idt();
+
idt_setup_done = true;
}

--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -1077,20 +1077,9 @@ void __init trap_init(void)
idt_setup_traps();

/*
- * Set the IDT descriptor to a fixed read-only location, so that the
- * "sidt" instruction will not leak the location of the kernel, and
- * to defend the IDT against arbitrary memory write vulnerabilities.
- * It will be reloaded in cpu_init() */
- cea_set_pte(CPU_ENTRY_AREA_RO_IDT_VADDR, __pa_symbol(idt_table),
- PAGE_KERNEL_RO);
- idt_descr.address = CPU_ENTRY_AREA_RO_IDT;
-
- /*
* Should be a barrier for any external CPU state:
*/
cpu_init();

idt_setup_ist_traps();
-
- idt_setup_debugidt_traps();
}
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