1 files changed, 61 insertions, 60 deletions

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 24b9fa89aa27..252e82bcfd2f 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -24,10 +24,11 @@
 #include <linux/module.h>
 #include <linux/memory.h>
 #include <linux/vmalloc.h>
+#include <linux/set_memory.h>
+#include <linux/execmem.h>
 
 #include <trace/syscall.h>
 
-#include <asm/set_memory.h>
 #include <asm/kprobes.h>
 #include <asm/ftrace.h>
 #include <asm/nops.h>
@@ -54,10 +55,10 @@ void ftrace_arch_code_modify_post_process(void)
 {
 	/*
 	 * ftrace_make_{call,nop}() may be called during
-	 * module load, and we need to finish the text_poke_queue()
+	 * module load, and we need to finish the smp_text_poke_batch_add()
 	 * that they do, here.
 	 */
-	text_poke_finish();
+	smp_text_poke_batch_finish();
 	ftrace_poke_late = 0;
 	mutex_unlock(&text_mutex);
 }
@@ -69,6 +70,10 @@ static const char *ftrace_nop_replace(void)
 
 static const char *ftrace_call_replace(unsigned long ip, unsigned long addr)
 {
+	/*
+	 * No need to translate into a callthunk. The trampoline does
+	 * the depth accounting itself.
+	 */
 	return text_gen_insn(CALL_INSN_OPCODE, (void *)ip, (void *)addr);
 }
 
@@ -91,6 +96,7 @@ static int ftrace_verify_code(unsigned long ip, const char *old_code)
 
 	/* Make sure it is what we expect it to be */
 	if (memcmp(cur_code, old_code, MCOUNT_INSN_SIZE) != 0) {
+		ftrace_expected = old_code;
 		WARN_ON(1);
 		return -EINVAL;
 	}
@@ -113,7 +119,7 @@ ftrace_modify_code_direct(unsigned long ip, const char *old_code,
 
 	/* replace the text with the new text */
 	if (ftrace_poke_late)
-		text_poke_queue((void *)ip, new_code, MCOUNT_INSN_SIZE, NULL);
+		smp_text_poke_batch_add((void *)ip, new_code, MCOUNT_INSN_SIZE, NULL);
 	else
 		text_poke_early((void *)ip, new_code, MCOUNT_INSN_SIZE);
 	return 0;
@@ -180,11 +186,11 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 
 	ip = (unsigned long)(&ftrace_call);
 	new = ftrace_call_replace(ip, (unsigned long)func);
-	text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+	smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
 
 	ip = (unsigned long)(&ftrace_regs_call);
 	new = ftrace_call_replace(ip, (unsigned long)func);
-	text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+	smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
 
 	return 0;
 }
@@ -216,7 +222,9 @@ void ftrace_replace_code(int enable)
 
 		ret = ftrace_verify_code(rec->ip, old);
 		if (ret) {
+			ftrace_expected = old;
 			ftrace_bug(ret, rec);
+			ftrace_expected = NULL;
 			return;
 		}
 	}
@@ -239,10 +247,10 @@ void ftrace_replace_code(int enable)
 			break;
 		}
 
-		text_poke_queue((void *)rec->ip, new, MCOUNT_INSN_SIZE, NULL);
+		smp_text_poke_batch_add((void *)rec->ip, new, MCOUNT_INSN_SIZE, NULL);
 		ftrace_update_record(rec, enable);
 	}
-	text_poke_finish();
+	smp_text_poke_batch_finish();
 }
 
 void arch_ftrace_update_code(int command)
@@ -253,29 +261,17 @@ void arch_ftrace_update_code(int command)
 /* Currently only x86_64 supports dynamic trampolines */
 #ifdef CONFIG_X86_64
 
-#ifdef CONFIG_MODULES
-#include <linux/moduleloader.h>
-/* Module allocation simplifies allocating memory for code */
 static inline void *alloc_tramp(unsigned long size)
 {
-	return module_alloc(size);
+	return execmem_alloc(EXECMEM_FTRACE, size);
 }
 static inline void tramp_free(void *tramp)
 {
-	module_memfree(tramp);
-}
-#else
-/* Trampolines can only be created if modules are supported */
-static inline void *alloc_tramp(unsigned long size)
-{
-	return NULL;
+	execmem_free(tramp);
 }
-static inline void tramp_free(void *tramp) { }
-#endif
 
 /* Defined as markers to the end of the ftrace default trampolines */
 extern void ftrace_regs_caller_end(void);
-extern void ftrace_regs_caller_ret(void);
 extern void ftrace_caller_end(void);
 extern void ftrace_caller_op_ptr(void);
 extern void ftrace_regs_caller_op_ptr(void);
@@ -301,7 +297,8 @@ union ftrace_op_code_union {
 	} __attribute__((packed));
 };
 
-#define RET_SIZE		(IS_ENABLED(CONFIG_RETPOLINE) ? 5 : 1 + IS_ENABLED(CONFIG_SLS))
+#define RET_SIZE \
+	(IS_ENABLED(CONFIG_MITIGATION_RETPOLINE) ? 5 : 1 + IS_ENABLED(CONFIG_MITIGATION_SLS))
 
 static unsigned long
 create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
@@ -316,7 +313,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
 	unsigned long size;
 	unsigned long *ptr;
 	void *trampoline;
-	void *ip;
+	void *ip, *dest;
 	/* 48 8b 15 <offset> is movq <offset>(%rip), %rdx */
 	unsigned const char op_ref[] = { 0x48, 0x8b, 0x15 };
 	unsigned const char retq[] = { RET_INSN_OPCODE, INT3_INSN_OPCODE };
@@ -357,8 +354,8 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
 		goto fail;
 
 	ip = trampoline + size;
-	if (cpu_feature_enabled(X86_FEATURE_RETHUNK))
-		__text_gen_insn(ip, JMP32_INSN_OPCODE, ip, &__x86_return_thunk, JMP32_INSN_SIZE);
+	if (cpu_wants_rethunk_at(ip))
+		__text_gen_insn(ip, JMP32_INSN_OPCODE, ip, x86_return_thunk, JMP32_INSN_SIZE);
 	else
 		memcpy(ip, retq, sizeof(retq));
 
@@ -403,20 +400,20 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
 	/* put in the call to the function */
 	mutex_lock(&text_mutex);
 	call_offset -= start_offset;
+	/*
+	 * No need to translate into a callthunk. The trampoline does
+	 * the depth accounting before the call already.
+	 */
+	dest = ftrace_ops_get_func(ops);
 	memcpy(trampoline + call_offset,
-	       text_gen_insn(CALL_INSN_OPCODE,
-			     trampoline + call_offset,
-			     ftrace_ops_get_func(ops)), CALL_INSN_SIZE);
+	       text_gen_insn(CALL_INSN_OPCODE, trampoline + call_offset, dest),
+	       CALL_INSN_SIZE);
 	mutex_unlock(&text_mutex);
 
 	/* ALLOC_TRAMP flags lets us know we created it */
 	ops->flags |= FTRACE_OPS_FL_ALLOC_TRAMP;
 
-	set_vm_flush_reset_perms(trampoline);
-
-	if (likely(system_state != SYSTEM_BOOTING))
-		set_memory_ro((unsigned long)trampoline, npages);
-	set_memory_x((unsigned long)trampoline, npages);
+	set_memory_rox((unsigned long)trampoline, npages);
 	return (unsigned long)trampoline;
 fail:
 	tramp_free(trampoline);
@@ -495,7 +492,7 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops)
 	mutex_lock(&text_mutex);
 	/* Do a safe modify in case the trampoline is executing */
 	new = ftrace_call_replace(ip, (unsigned long)func);
-	text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+	smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
 	mutex_unlock(&text_mutex);
 }
 
@@ -518,9 +515,6 @@ static void *addr_from_call(void *ptr)
 	return ptr + CALL_INSN_SIZE + call.disp;
 }
 
-void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
-			   unsigned long frame_pointer);
-
 /*
  * If the ops->trampoline was not allocated, then it probably
  * has a static trampoline func, or is the ftrace caller itself.
@@ -592,7 +586,7 @@ static int ftrace_mod_jmp(unsigned long ip, void *func)
 	const char *new;
 
 	new = ftrace_jmp_replace(ip, (unsigned long)func);
-	text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+	smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
 	return 0;
 }
 
@@ -611,16 +605,8 @@ int ftrace_disable_ftrace_graph_caller(void)
 }
 #endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */
 
-/*
- * Hook the return address and push it in the stack of return addrs
- * in current thread info.
- */
-void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
-			   unsigned long frame_pointer)
+static inline bool skip_ftrace_return(void)
 {
-	unsigned long return_hooker = (unsigned long)&return_to_handler;
-	int bit;
-
 	/*
 	 * When resuming from suspend-to-ram, this function can be indirectly
 	 * called from early CPU startup code while the CPU is in real mode,
@@ -630,33 +616,48 @@ void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
 	 * This check isn't as accurate as virt_addr_valid(), but it should be
 	 * good enough for this purpose, and it's fast.
 	 */
-	if (unlikely((long)__builtin_frame_address(0) >= 0))
-		return;
+	if ((long)__builtin_frame_address(0) >= 0)
+		return true;
 
-	if (unlikely(ftrace_graph_is_dead()))
-		return;
+	if (ftrace_graph_is_dead())
+		return true;
 
-	if (unlikely(atomic_read(&current->tracing_graph_pause)))
-		return;
+	if (atomic_read(&current->tracing_graph_pause))
+		return true;
+	return false;
+}
 
-	bit = ftrace_test_recursion_trylock(ip, *parent);
-	if (bit < 0)
+/*
+ * Hook the return address and push it in the stack of return addrs
+ * in current thread info.
+ */
+void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
+			   unsigned long frame_pointer)
+{
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
+
+	if (unlikely(skip_ftrace_return()))
 		return;
 
 	if (!function_graph_enter(*parent, ip, frame_pointer, parent))
 		*parent = return_hooker;
-
-	ftrace_test_recursion_unlock(bit);
 }
 
 #ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 		       struct ftrace_ops *op, struct ftrace_regs *fregs)
 {
-	struct pt_regs *regs = &fregs->regs;
+	struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
 	unsigned long *stack = (unsigned long *)kernel_stack_pointer(regs);
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
+	unsigned long *parent = (unsigned long *)stack;
 
-	prepare_ftrace_return(ip, (unsigned long *)stack, 0);
+	if (unlikely(skip_ftrace_return()))
+		return;
+
+
+	if (!function_graph_enter_regs(*parent, ip, 0, parent, fregs))
+		*parent = return_hooker;
 }
 #endif