bpf/trampoline: Allow ftrace location to differ from trampoline attach address

On some architectures, ftrace location can include multiple
instructions, and does not necessarily match the function entry address
returned by kallsyms_lookup(). Drop the check in is_ftrace_location() to
accommodate the same.

Signed-off-by: Naveen N. Rao <[email protected]>

Author: rnav

kernel/bpf/trampoline.c

@@ -124,8 +124,6 @@ static int is_ftrace_location(void *ip)
 	addr = ftrace_location((long)ip);
 	if (!addr)
 		return 0;
-	if (WARN_ON_ONCE(addr != (long)ip))
-		return -EFAULT;
 	return 1;
 }