[RFC PATCH tip/master V3 2/8] kprobes/x86: Fix the description of __copy_instruction()
From: Masami Hiramatsu
Date: Wed Mar 29 2017 - 00:59:34 EST
Fix the description comment of __copy_instruction() function
since it has already been changed to return the length of
copied instruction.
Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
arch/x86/kernel/kprobes/core.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 9eae5a6..81d4dc7 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -350,11 +350,10 @@ static int is_IF_modifier(kprobe_opcode_t *insn)
}
/*
- * Copy an instruction and adjust the displacement if the instruction
- * uses the %rip-relative addressing mode.
- * If it does, Return the address of the 32-bit displacement word.
- * If not, return null.
- * Only applicable to 64-bit x86.
+ * Copy an instruction with recovering modified instruction by kprobes
+ * and adjust the displacement if the instruction uses the %rip-relative
+ * addressing mode.
+ * This returns the length of copied instruction, or 0 if it has an error.
*/
int __copy_instruction(u8 *dest, u8 *src)
{
@@ -376,6 +375,7 @@ int __copy_instruction(u8 *dest, u8 *src)
memcpy(dest, insn.kaddr, length);
#ifdef CONFIG_X86_64
+ /* Only x86_64 has RIP relative instructions */
if (insn_rip_relative(&insn)) {
s64 newdisp;
u8 *disp;