Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
  ftrace: fix current_tracer error return
  tracing: fix a build error on alpha
  ftrace: use a real variable for ftrace_nop in x86
  tracing/ftrace: make boot tracer select the sched_switch tracer
  tracepoint: check if the probe has been registered
  asm-generic: define DIE_OOPS in asm-generic
  trace: fix printk warning for u64
  ftrace: warning in kernel/trace/ftrace.c
  ftrace: fix build failure
  ftrace, powerpc, sparc64, x86: remove notrace from arch ftrace file
  ftrace: remove ftrace hash
  ftrace: remove mcount set
  ftrace: remove daemon
  ftrace: disable dynamic ftrace for all archs that use daemon
  ftrace: add ftrace warn on to disable ftrace
  ftrace: only have ftrace_kill atomic
  ftrace: use probe_kernel
  ftrace: comment arch ftrace code
  ftrace: return error on failed modified text.
  ftrace: dynamic ftrace process only text section
  ...

6 files changed, 29 insertions, 36 deletions

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index d7e5a58ee22f..e489ff9cb3e2 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -6,11 +6,12 @@ extra-y                := head_$(BITS).o head$(BITS).o head.o init_task.o vmlinu
 
 CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE)
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 # Do not profile debug and lowlevel utilities
 CFLAGS_REMOVE_tsc.o = -pg
 CFLAGS_REMOVE_rtc.o = -pg
 CFLAGS_REMOVE_paravirt-spinlocks.o = -pg
+CFLAGS_REMOVE_ftrace.o = -pg
 endif
 
 #
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index dd65143941a8..28b597ef9ca1 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -1149,7 +1149,7 @@ ENDPROC(xen_failsafe_callback)
 
 #endif  /* CONFIG_XEN */
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 
 ENTRY(mcount)
@@ -1204,7 +1204,7 @@ trace:
         jmp ftrace_stub
 END(mcount)
 #endif /* CONFIG_DYNAMIC_FTRACE */
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 .section .rodata,"a"
 #include "syscall_table_32.S"
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 09e7145484c5..b86f332c96a6 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -61,7 +61,7 @@
 
         .code64
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 ENTRY(mcount)
         retq
@@ -138,7 +138,7 @@ trace:
         jmp ftrace_stub
 END(mcount)
 #endif /* CONFIG_DYNAMIC_FTRACE */
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 #ifndef CONFIG_PREEMPT
 #define retint_kernel retint_restore_args
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index d073d981a730..50ea0ac8c9bf 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -21,8 +21,7 @@
 #include <asm/nops.h>
 
 
-/* Long is fine, even if it is only 4 bytes ;-) */
-static unsigned long *ftrace_nop;
+static unsigned char ftrace_nop[MCOUNT_INSN_SIZE];
 
 union ftrace_code_union {
         char code[MCOUNT_INSN_SIZE];
@@ -33,17 +32,17 @@ union ftrace_code_union {
 };
 
 
-static int notrace ftrace_calc_offset(long ip, long addr)
+static int ftrace_calc_offset(long ip, long addr)
 {
         return (int)(addr - ip);
 }
 
-notrace unsigned char *ftrace_nop_replace(void)
+unsigned char *ftrace_nop_replace(void)
 {
-        return (char *)ftrace_nop;
+        return ftrace_nop;
 }
 
-notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
 {
         static union ftrace_code_union calc;
 
@@ -57,7 +56,7 @@ notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
         return calc.code;
 }
 
-notrace int
+int
 ftrace_modify_code(unsigned long ip, unsigned char *old_code,
                    unsigned char *new_code)
 {
@@ -66,26 +65,31 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code,
         /*
          * Note: Due to modules and __init, code can
          *  disappear and change, we need to protect against faulting
-         *  as well as code changing.
+         *  as well as code changing. We do this by using the
+         *  probe_kernel_* functions.
          *
          * No real locking needed, this code is run through
          * kstop_machine, or before SMP starts.
          */
-        if (__copy_from_user_inatomic(replaced, (char __user *)ip, MCOUNT_INSN_SIZE))
-                return 1;
 
+        /* read the text we want to modify */
+        if (probe_kernel_read(replaced, (void *)ip, MCOUNT_INSN_SIZE))
+                return -EFAULT;
+
+        /* Make sure it is what we expect it to be */
         if (memcmp(replaced, old_code, MCOUNT_INSN_SIZE) != 0)
-                return 2;
+                return -EINVAL;
 
-        WARN_ON_ONCE(__copy_to_user_inatomic((char __user *)ip, new_code,
-                                    MCOUNT_INSN_SIZE));
+        /* replace the text with the new text */
+        if (probe_kernel_write((void *)ip, new_code, MCOUNT_INSN_SIZE))
+                return -EPERM;
 
         sync_core();
 
         return 0;
 }
 
-notrace int ftrace_update_ftrace_func(ftrace_func_t func)
+int ftrace_update_ftrace_func(ftrace_func_t func)
 {
         unsigned long ip = (unsigned long)(&ftrace_call);
         unsigned char old[MCOUNT_INSN_SIZE], *new;
@@ -98,13 +102,6 @@ notrace int ftrace_update_ftrace_func(ftrace_func_t func)
         return ret;
 }
 
-notrace int ftrace_mcount_set(unsigned long *data)
-{
-        /* mcount is initialized as a nop */
-        *data = 0;
-        return 0;
-}
-
 int __init ftrace_dyn_arch_init(void *data)
 {
         extern const unsigned char ftrace_test_p6nop[];
@@ -127,9 +124,6 @@ int __init ftrace_dyn_arch_init(void *data)
          * TODO: check the cpuid to determine the best nop.
          */
         asm volatile (
-                "jmp ftrace_test_jmp\n"
-                /* This code needs to stay around */
-                ".section .text, \"ax\"\n"
                 "ftrace_test_jmp:"
                 "jmp ftrace_test_p6nop\n"
                 "nop\n"
@@ -140,8 +134,6 @@ int __init ftrace_dyn_arch_init(void *data)
                 "jmp 1f\n"
                 "ftrace_test_nop5:"
                 ".byte 0x66,0x66,0x66,0x66,0x90\n"
-                "jmp 1f\n"
-                ".previous\n"
                 "1:"
                 ".section .fixup, \"ax\"\n"
                 "2:     movl $1, %0\n"
@@ -156,15 +148,15 @@ int __init ftrace_dyn_arch_init(void *data)
         switch (faulted) {
         case 0:
                 pr_info("ftrace: converting mcount calls to 0f 1f 44 00 00\n");
-                ftrace_nop = (unsigned long *)ftrace_test_p6nop;
+                memcpy(ftrace_nop, ftrace_test_p6nop, MCOUNT_INSN_SIZE);
                 break;
         case 1:
                 pr_info("ftrace: converting mcount calls to 66 66 66 66 90\n");
-                ftrace_nop = (unsigned long *)ftrace_test_nop5;
+                memcpy(ftrace_nop, ftrace_test_nop5, MCOUNT_INSN_SIZE);
                 break;
         case 2:
                 pr_info("ftrace: converting mcount calls to jmp . + 5\n");
-                ftrace_nop = (unsigned long *)ftrace_test_jmp;
+                memcpy(ftrace_nop, ftrace_test_jmp, MCOUNT_INSN_SIZE);
                 break;
         }
 
diff --git a/arch/x86/kernel/i386_ksyms_32.c b/arch/x86/kernel/i386_ksyms_32.c
index dd7ebee446af..43cec6bdda63 100644
--- a/arch/x86/kernel/i386_ksyms_32.c
+++ b/arch/x86/kernel/i386_ksyms_32.c
@@ -5,7 +5,7 @@
 #include <asm/desc.h>
 #include <asm/ftrace.h>
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 /* mcount is defined in assembly */
 EXPORT_SYMBOL(mcount);
 #endif
diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c
index b545f371b5f5..695e426aa354 100644
--- a/arch/x86/kernel/x8664_ksyms_64.c
+++ b/arch/x86/kernel/x8664_ksyms_64.c
@@ -12,7 +12,7 @@
 #include <asm/desc.h>
 #include <asm/ftrace.h>
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 /* mcount is defined in assembly */
 EXPORT_SYMBOL(mcount);
 #endif