v4.19.13 snapshot.
diff --git a/scripts/checkstack.pl b/scripts/checkstack.pl
new file mode 100755
index 0000000..8081b6c
--- /dev/null
+++ b/scripts/checkstack.pl
@@ -0,0 +1,168 @@
+#!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0
+
+# Check the stack usage of functions
+#
+# Copyright Joern Engel <joern@lazybastard.org>
+# Inspired by Linus Torvalds
+# Original idea maybe from Keith Owens
+# s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
+# Mips port by Juan Quintela <quintela@mandrakesoft.com>
+# IA64 port via Andreas Dilger
+# Arm port by Holger Schurig
+# sh64 port by Paul Mundt
+# Random bits by Matt Mackall <mpm@selenic.com>
+# M68k port by Geert Uytterhoeven and Andreas Schwab
+# AArch64, PARISC ports by Kyle McMartin
+# sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
+# ppc64le port by Breno Leitao <leitao@debian.org>
+#
+# Usage:
+# objdump -d vmlinux | scripts/checkstack.pl [arch]
+#
+# TODO : Port to all architectures (one regex per arch)
+
+use strict;
+
+# check for arch
+#
+# $re is used for two matches:
+# $& (whole re) matches the complete objdump line with the stack growth
+# $1 (first bracket) matches the size of the stack growth
+#
+# $dre is similar, but for dynamic stack redutions:
+# $& (whole re) matches the complete objdump line with the stack growth
+# $1 (first bracket) matches the dynamic amount of the stack growth
+#
+# use anything else and feel the pain ;)
+my (@stack, $re, $dre, $x, $xs, $funcre);
+{
+ my $arch = shift;
+ if ($arch eq "") {
+ $arch = `uname -m`;
+ chomp($arch);
+ }
+
+ $x = "[0-9a-f]"; # hex character
+ $xs = "[0-9a-f ]"; # hex character or space
+ $funcre = qr/^$x* <(.*)>:$/;
+ if ($arch eq 'aarch64') {
+ #ffffffc0006325cc: a9bb7bfd stp x29, x30, [sp,#-80]!
+ $re = qr/^.*stp.*sp,\#-([0-9]{1,8})\]\!/o;
+ } elsif ($arch eq 'arm') {
+ #c0008ffc: e24dd064 sub sp, sp, #100 ; 0x64
+ $re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
+ } elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
+ #c0105234: 81 ec ac 05 00 00 sub $0x5ac,%esp
+ # or
+ # 2f60: 48 81 ec e8 05 00 00 sub $0x5e8,%rsp
+ $re = qr/^.*[as][du][db] \$(0x$x{1,8}),\%(e|r)sp$/o;
+ $dre = qr/^.*[as][du][db] (%.*),\%(e|r)sp$/o;
+ } elsif ($arch eq 'ia64') {
+ #e0000000044011fc: 01 0f fc 8c adds r12=-384,r12
+ $re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
+ } elsif ($arch eq 'm68k') {
+ # 2b6c: 4e56 fb70 linkw %fp,#-1168
+ # 1df770: defc ffe4 addaw #-28,%sp
+ $re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
+ } elsif ($arch eq 'mips64') {
+ #8800402c: 67bdfff0 daddiu sp,sp,-16
+ $re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
+ } elsif ($arch eq 'mips') {
+ #88003254: 27bdffe0 addiu sp,sp,-32
+ $re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
+ } elsif ($arch eq 'nios2') {
+ #25a8: defffb04 addi sp,sp,-20
+ $re = qr/.*addi.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
+ } elsif ($arch eq 'openrisc') {
+ # c000043c: 9c 21 fe f0 l.addi r1,r1,-272
+ $re = qr/.*l\.addi.*r1,r1,-(([0-9]{2}|[3-9])[0-9]{2})/o;
+ } elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
+ $re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
+ } elsif ($arch eq 'powerpc' || $arch =~ /^ppc(64)?(le)?$/ ) {
+ # powerpc : 94 21 ff 30 stwu r1,-208(r1)
+ # ppc64(le) : 81 ff 21 f8 stdu r1,-128(r1)
+ $re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
+ } elsif ($arch =~ /^s390x?$/) {
+ # 11160: a7 fb ff 60 aghi %r15,-160
+ # or
+ # 100092: e3 f0 ff c8 ff 71 lay %r15,-56(%r15)
+ $re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
+ (?:\(\%r15\))?$/ox;
+ } elsif ($arch =~ /^sh64$/) {
+ #XXX: we only check for the immediate case presently,
+ # though we will want to check for the movi/sub
+ # pair for larger users. -- PFM.
+ #a00048e0: d4fc40f0 addi.l r15,-240,r15
+ $re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
+ } elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
+ # f0019d10: 9d e3 bf 90 save %sp, -112, %sp
+ $re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
+ } else {
+ print("wrong or unknown architecture \"$arch\"\n");
+ exit
+ }
+}
+
+#
+# main()
+#
+my ($func, $file, $lastslash);
+
+while (my $line = <STDIN>) {
+ if ($line =~ m/$funcre/) {
+ $func = $1;
+ }
+ elsif ($line =~ m/(.*):\s*file format/) {
+ $file = $1;
+ $file =~ s/\.ko//;
+ $lastslash = rindex($file, "/");
+ if ($lastslash != -1) {
+ $file = substr($file, $lastslash + 1);
+ }
+ }
+ elsif ($line =~ m/$re/) {
+ my $size = $1;
+ $size = hex($size) if ($size =~ /^0x/);
+
+ if ($size > 0xf0000000) {
+ $size = - $size;
+ $size += 0x80000000;
+ $size += 0x80000000;
+ }
+ next if ($size > 0x10000000);
+
+ next if $line !~ m/^($xs*)/;
+ my $addr = $1;
+ $addr =~ s/ /0/g;
+ $addr = "0x$addr";
+
+ my $intro = "$addr $func [$file]:";
+ my $padlen = 56 - length($intro);
+ while ($padlen > 0) {
+ $intro .= ' ';
+ $padlen -= 8;
+ }
+ next if ($size < 100);
+ push @stack, "$intro$size\n";
+ }
+ elsif (defined $dre && $line =~ m/$dre/) {
+ my $size = "Dynamic ($1)";
+
+ next if $line !~ m/^($xs*)/;
+ my $addr = $1;
+ $addr =~ s/ /0/g;
+ $addr = "0x$addr";
+
+ my $intro = "$addr $func [$file]:";
+ my $padlen = 56 - length($intro);
+ while ($padlen > 0) {
+ $intro .= ' ';
+ $padlen -= 8;
+ }
+ push @stack, "$intro$size\n";
+ }
+}
+
+# Sort output by size (last field)
+print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;