checkpatch: add pF/pf deprecation warning

We deprecated '%pF/%pf' printk specifiers, since '%pS/%ps' is now smart
enough to handle function pointer dereference on platforms where such
dereference is required.

Link: http://lkml.kernel.org/r/20171109234830.5067-7-sergey.senozhatsky@gmail.com
To: Tony Luck <tony.luck@intel.com>
To: Fenghua Yu <fenghua.yu@intel.com>
To: Helge Deller <deller@gmx.de>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Paul Mackerras <paulus@samba.org>
To: Michael Ellerman <mpe@ellerman.id.au>
To: James Bottomley <jejb@parisc-linux.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-ia64@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>

1 files changed, 9 insertions, 2 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 95cda3ecc66b..0bb68e7ff173 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5753,18 +5753,25 @@ sub process {
                         for (my $count = $linenr; $count <= $lc; $count++) {
                                 my $fmt = get_quoted_string($lines[$count - 1], raw_line($count, 0));
                                 $fmt =~ s/%%//g;
-                                if ($fmt =~ /(\%[\*\d\.]*p(?![\WFfSsBKRraEhMmIiUDdgVCbGNO]).)/) {
+                                if ($fmt =~ /(\%[\*\d\.]*p(?![\WSsBKRraEhMmIiUDdgVCbGNO]).)/) {
                                         $bad_extension = $1;
                                         last;
                                 }
                         }
                         if ($bad_extension ne "") {
                                 my $stat_real = raw_line($linenr, 0);
+                                my $ext_type = "Invalid";
+                                my $use = "";
                                 for (my $count = $linenr + 1; $count <= $lc; $count++) {
                                         $stat_real = $stat_real . "\n" . raw_line($count, 0);
                                 }
+                                if ($bad_extension =~ /p[Ff]/) {
+                                        $ext_type = "Deprecated";
+                                        $use = " - use %pS instead";
+                                        $use =~ s/pS/ps/ if ($bad_extension =~ /pf/);
+                                }
                                 WARN("VSPRINTF_POINTER_EXTENSION",
-                                     "Invalid vsprintf pointer extension '$bad_extension'\n" . "$here\n$stat_real\n");
+                                     "$ext_type vsprintf pointer extension '$bad_extension'$use\n" . "$here\n$stat_real\n");
                         }
                 }