binfmt_elf: PIE: make PF_RANDOMIZE check comment more accurate

The comment I originally added in commit a3defbe5 ("binfmt_elf: fix
PIE execution with randomization disabled") is not really 100% accurate
-- sysctl is not the only way how PF_RANDOMIZE could be forcibly unset
in runtime.

Another option of course is direct modification of personality flags
(i.e.  running through setarch wrapper).

Make the comment more explicit and accurate.
Signed-off-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/binfmt_elf.c

@@ -803,7 +803,8 @@ static int load_elf_binary(struct linux_binprm *bprm)
 			 * follow the loader, and is not movable.  */
 #ifdef CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE
 			/* Memory randomization might have been switched off
-			 * in runtime via sysctl.
+			 * in runtime via sysctl or explicit setting of
+			 * personality flags.
 			 * If that is the case, retain the original non-zero
 			 * load_bias value in order to establish proper
 			 * non-randomized mappings.