x86/ftrace: Use text_gen_insn()

Replace the ftrace_code_union with the generic text_gen_insn() helper,
which does exactly this.

Tested-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191111132457.932808000@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 0 insertions, 26 deletions

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index f8f34f94d13d..cfcfadf5cc80 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -1247,29 +1247,3 @@ void __ref text_poke_bp(void *addr, const void *opcode, size_t len, const void *
 	text_poke_loc_init(&tp, addr, opcode, len, emulate);
 	text_poke_bp_batch(&tp, 1);
 }
-
-union text_poke_insn {
-	u8 text[POKE_MAX_OPCODE_SIZE];
-	struct {
-		u8 opcode;
-		s32 disp;
-	} __attribute__((packed));
-};
-
-void *text_gen_insn(u8 opcode, const void *addr, const void *dest)
-{
-	static union text_poke_insn insn; /* text_mutex */
-	int size = text_opcode_size(opcode);
-
-	lockdep_assert_held(&text_mutex);
-
-	insn.opcode = opcode;
-
-	if (size > 1) {
-		insn.disp = (long)dest - (long)(addr + size);
-		if (size == 2)
-			BUG_ON((insn.disp >> 31) != (insn.disp >> 7));
-	}
-
-	return &insn.text;
-}