x86/ftrace: Remove SYSTEM_BOOTING exceptions

Now that text_poke is available before ftrace, remove the
SYSTEM_BOOTING exceptions.

Specifically, this cures a W+X case during boot.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221025201057.945960823@infradead.org

arch/x86/kernel/alternative.c

@@ -1681,11 +1681,6 @@ void __ref text_poke_queue(void *addr, const void *opcode, size_t len, const voi
 {
 	struct text_poke_loc *tp;
 
-	if (unlikely(system_state == SYSTEM_BOOTING)) {
-		text_poke_early(addr, opcode, len);
-		return;
-	}
-
 	text_poke_flush(addr);
 
 	tp = &tp_vec[tp_vec_nr++];
@@ -1707,11 +1702,6 @@ void __ref text_poke_bp(void *addr, const void *opcode, size_t len, const void *
 {
 	struct text_poke_loc tp;
 
-	if (unlikely(system_state == SYSTEM_BOOTING)) {
-		text_poke_early(addr, opcode, len);
-		return;
-	}
-
 	text_poke_loc_init(&tp, addr, opcode, len, emulate);
 	text_poke_bp_batch(&tp, 1);
 }

arch/x86/kernel/ftrace.c

@@ -415,8 +415,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
 
 	set_vm_flush_reset_perms(trampoline);
 
-	if (likely(system_state != SYSTEM_BOOTING))
-		set_memory_ro((unsigned long)trampoline, npages);
+	set_memory_ro((unsigned long)trampoline, npages);
 	set_memory_x((unsigned long)trampoline, npages);
 	return (unsigned long)trampoline;
 fail: