[PATCH 05/13 v2] ftrace: use probe_kernel

[Steven Rostedt <rostedt@goodmis.org>]

[-- Attachment #1: ftrace-use-probe-kernel.patch --]
[-- Type: text/plain, Size: 1184 bytes --]

Andrew Morton suggested using the proper API for reading and writing
kernel areas that might fault.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 arch/x86/kernel/ftrace.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Index: linux-compile.git/arch/x86/kernel/ftrace.c
===================================================================
--- linux-compile.git.orig/arch/x86/kernel/ftrace.c	2008-10-22 15:24:15.000000000 -0400
+++ linux-compile.git/arch/x86/kernel/ftrace.c	2008-10-22 15:26:07.000000000 -0400
@@ -74,8 +74,7 @@ ftrace_modify_code(unsigned long ip, uns
 	 */
 
 	/* read the text we want to modify */
-	if (__copy_from_user_inatomic(replaced, (char __user *)ip,
-				      MCOUNT_INSN_SIZE))
+	if (probe_kernel_read(replaced, (void *)ip, MCOUNT_INSN_SIZE))
 		return -EFAULT;
 
 	/* Make sure it is what we expect it to be */
@@ -83,8 +82,7 @@ ftrace_modify_code(unsigned long ip, uns
 		return -EINVAL;
 
 	/* replace the text with the new text */
-	if (__copy_to_user_inatomic((char __user *)ip, new_code,
-				    MCOUNT_INSN_SIZE))
+	if (probe_kernel_write((void *)ip, new_code, MCOUNT_INSN_SIZE))
 		return -EPERM;
 
 	sync_core();

--