[PATCH] x86/kprobes: Remove dead code

From: Muhammad Usama Anjum
Date: Wed Mar 24 2021 - 13:37:49 EST


The condition in switch statement `opcode & 0xf0` cannot evaluate to
0xff. So this case statement will never execute. Remove it.

Fixes: 6256e668b7 ("x86/kprobes: Use int3 instead of debug trap for single-step")
Signed-off-by: Muhammad Usama Anjum <musamaanjum@xxxxxxxxx>
---
arch/x86/kernel/kprobes/core.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 89d9f26785c7..3b7bcc077020 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -177,9 +177,6 @@ int can_boost(struct insn *insn, void *addr)
case 0xf0:
/* clear and set flags are boostable */
return (opcode == 0xf5 || (0xf7 < opcode && opcode < 0xfe));
- case 0xff:
- /* indirect jmp is boostable */
- return X86_MODRM_REG(insn->modrm.bytes[0]) == 4;
default:
/* CS override prefix and call are not boostable */
return (opcode != 0x2e && opcode != 0x9a);
--
2.25.1