x86/idt: Remove the tracing IDT completely

No more users of the tracing IDT. All exception tracepoints have been moved
into the regular handlers. Get rid of the mess which shouldn't have been
created in the first place.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.378851687@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 6 insertions, 76 deletions

diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index 71094f208673..d18a604a0941 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -421,35 +421,7 @@ static inline void set_nmi_gate(int gate, void *addr)
 }
 #endif
 
-#ifdef CONFIG_TRACING
-extern struct desc_ptr trace_idt_descr;
-extern gate_desc trace_idt_table[];
-static inline void write_trace_idt_entry(int entry, const gate_desc *gate)
-{
-	write_idt_entry(trace_idt_table, entry, gate);
-}
-
-static inline void _trace_set_gate(int gate, unsigned type, void *addr,
-				   unsigned dpl, unsigned ist, unsigned seg)
-{
-	gate_desc s;
-
-	pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
-	/*
-	 * does not need to be atomic because it is only done once at
-	 * setup time
-	 */
-	write_trace_idt_entry(gate, &s);
-}
-#else
-static inline void write_trace_idt_entry(int entry, const gate_desc *gate)
-{
-}
-
-#define _trace_set_gate(gate, type, addr, dpl, ist, seg)
-#endif
-
-static inline void _set_gate(int gate, unsigned type, void *addr,
+static inline void _set_gate(int gate, unsigned type, const void *addr,
 			     unsigned dpl, unsigned ist, unsigned seg)
 {
 	gate_desc s;
@@ -460,28 +432,13 @@ static inline void _set_gate(int gate, unsigned type, void *addr,
 	 * setup time
 	 */
 	write_idt_entry(idt_table, gate, &s);
-	write_trace_idt_entry(gate, &s);
 }
 
-/*
- * This needs to use 'idt_table' rather than 'idt', and
- * thus use the _nonmapped_ version of the IDT, as the
- * Pentium F0 0F bugfix can have resulted in the mapped
- * IDT being write-protected.
- */
-#define set_intr_gate_notrace(n, addr)					\
-	do {								\
-		BUG_ON((unsigned)n > 0xFF);				\
-		_set_gate(n, GATE_INTERRUPT, (void *)addr, 0, 0,	\
-			  __KERNEL_CS);					\
-	} while (0)
-
-#define set_intr_gate(n, addr)						\
-	do {								\
-		set_intr_gate_notrace(n, addr);				\
-		_trace_set_gate(n, GATE_INTERRUPT, (void *)trace_##addr,\
-				0, 0, __KERNEL_CS);			\
-	} while (0)
+static inline void set_intr_gate(unsigned int n, const void *addr)
+{
+	BUG_ON(n > 0xFF);
+	_set_gate(n, GATE_INTERRUPT, addr, 0, 0, __KERNEL_CS);
+}
 
 extern unsigned long used_vectors[];
 
@@ -565,31 +522,6 @@ static inline void load_debug_idt(void)
 }
 #endif
 
-#ifdef CONFIG_TRACING
-extern atomic_t trace_idt_ctr;
-static inline bool is_trace_idt_enabled(void)
-{
-	if (atomic_read(&trace_idt_ctr))
-		return true;
-
-	return false;
-}
-
-static inline void load_trace_idt(void)
-{
-	load_idt((const struct desc_ptr *)&trace_idt_descr);
-}
-#else
-static inline bool is_trace_idt_enabled(void)
-{
-	return false;
-}
-
-static inline void load_trace_idt(void)
-{
-}
-#endif
-
 /*
  * The load_current_idt() must be called with interrupts disabled
  * to avoid races. That way the IDT will always be set back to the expected
@@ -601,8 +533,6 @@ static inline void load_current_idt(void)
 {
 	if (is_debug_idt_enabled())
 		load_debug_idt();
-	else if (is_trace_idt_enabled())
-		load_trace_idt();
 	else
 		load_idt((const struct desc_ptr *)&idt_descr);
 }