Revision be0f272bfc83797f70d44faca86954df62e2bbc0 authored by Ard Biesheuvel on 20 November 2017, 17:41:30 UTC, committed by Will Deacon on 01 December 2017, 13:04:59 UTC
When building the arm64 kernel with both CONFIG_ARM64_MODULE_PLTS and CONFIG_DYNAMIC_FTRACE enabled, the ftrace-mod.o object file is built with the kernel and contains a trampoline that is linked into each module, so that modules can be loaded far away from the kernel and still reach the ftrace entry point in the core kernel with an ordinary relative branch, as is emitted by the compiler instrumentation code dynamic ftrace relies on. In order to be able to build out of tree modules, this object file needs to be included into the linux-headers or linux-devel packages, which is undesirable, as it makes arm64 a special case (although a precedent does exist for 32-bit PPC). Given that the trampoline essentially consists of a PLT entry, let's not bother with a source or object file for it, and simply patch it in whenever the trampoline is being populated, using the existing PLT support routines. Cc: <stable@vger.kernel.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
1 parent 7e8b9c1
export_report.pl
#!/usr/bin/env perl
#
# (C) Copyright IBM Corporation 2006.
# Released under GPL v2.
# Author : Ram Pai (linuxram@us.ibm.com)
#
# Usage: export_report.pl -k Module.symvers [-o report_file ] -f *.mod.c
#
use warnings;
use Getopt::Std;
use strict;
sub numerically {
my $no1 = (split /\s+/, $a)[1];
my $no2 = (split /\s+/, $b)[1];
return $no1 <=> $no2;
}
sub alphabetically {
my ($module1, $value1) = @{$a};
my ($module2, $value2) = @{$b};
return $value1 <=> $value2 || $module2 cmp $module1;
}
sub print_depends_on {
my ($href) = @_;
print "\n";
for my $mod (sort keys %$href) {
my $list = $href->{$mod};
print "\t$mod:\n";
foreach my $sym (sort numerically @{$list}) {
my ($symbol, $no) = split /\s+/, $sym;
printf("\t\t%-25s\n", $symbol);
}
print "\n";
}
print "\n";
print "~"x80 , "\n";
}
sub usage {
print "Usage: @_ -h -k Module.symvers [ -o outputfile ] \n",
"\t-f: treat all the non-option argument as .mod.c files. ",
"Recommend using this as the last option\n",
"\t-h: print detailed help\n",
"\t-k: the path to Module.symvers file. By default uses ",
"the file from the current directory\n",
"\t-o outputfile: output the report to outputfile\n";
exit 0;
}
sub collectcfiles {
my @file;
while (<.tmp_versions/*.mod>) {
open my $fh, '<', $_ or die "cannot open $_: $!\n";
push (@file,
grep s/\.ko/.mod.c/, # change the suffix
grep m/.+\.ko/, # find the .ko path
<$fh>); # lines in opened file
}
chomp @file;
return @file;
}
my (%SYMBOL, %MODULE, %opt, @allcfiles);
if (not getopts('hk:o:f',\%opt) or defined $opt{'h'}) {
usage($0);
}
if (defined $opt{'f'}) {
@allcfiles = @ARGV;
} else {
@allcfiles = collectcfiles();
}
if (not defined $opt{'k'}) {
$opt{'k'} = "Module.symvers";
}
open (my $module_symvers, '<', $opt{'k'})
or die "Sorry, cannot open $opt{'k'}: $!\n";
if (defined $opt{'o'}) {
open (my $out, '>', $opt{'o'})
or die "Sorry, cannot open $opt{'o'} $!\n";
select $out;
}
#
# collect all the symbols and their attributes from the
# Module.symvers file
#
while ( <$module_symvers> ) {
chomp;
my (undef, $symbol, $module, $gpl) = split;
$SYMBOL { $symbol } = [ $module , "0" , $symbol, $gpl];
}
close($module_symvers);
#
# collect the usage count of each symbol.
#
my $modversion_warnings = 0;
foreach my $thismod (@allcfiles) {
my $module;
unless (open ($module, '<', $thismod)) {
warn "Sorry, cannot open $thismod: $!\n";
next;
}
my $state=0;
while ( <$module> ) {
chomp;
if ($state == 0) {
$state = 1 if ($_ =~ /static const struct modversion_info/);
next;
}
if ($state == 1) {
$state = 2 if ($_ =~ /__attribute__\(\(section\("__versions"\)\)\)/);
next;
}
if ($state == 2) {
if ( $_ !~ /0x[0-9a-f]+,/ ) {
next;
}
my $sym = (split /([,"])/,)[4];
my ($module, $value, $symbol, $gpl) = @{$SYMBOL{$sym}};
$SYMBOL{ $sym } = [ $module, $value+1, $symbol, $gpl];
push(@{$MODULE{$thismod}} , $sym);
}
}
if ($state != 2) {
warn "WARNING:$thismod is not built with CONFIG_MODVERSIONS enabled\n";
$modversion_warnings++;
}
close($module);
}
print "\tThis file reports the exported symbols usage patterns by in-tree\n",
"\t\t\t\tmodules\n";
printf("%s\n\n\n","x"x80);
printf("\t\t\t\tINDEX\n\n\n");
printf("SECTION 1: Usage counts of all exported symbols\n");
printf("SECTION 2: List of modules and the exported symbols they use\n");
printf("%s\n\n\n","x"x80);
printf("SECTION 1:\tThe exported symbols and their usage count\n\n");
printf("%-25s\t%-25s\t%-5s\t%-25s\n", "Symbol", "Module", "Usage count",
"export type");
#
# print the list of unused exported symbols
#
foreach my $list (sort alphabetically values(%SYMBOL)) {
my ($module, $value, $symbol, $gpl) = @{$list};
printf("%-25s\t%-25s\t%-10s\t", $symbol, $module, $value);
if (defined $gpl) {
printf("%-25s\n",$gpl);
} else {
printf("\n");
}
}
printf("%s\n\n\n","x"x80);
printf("SECTION 2:\n\tThis section reports export-symbol-usage of in-kernel
modules. Each module lists the modules, and the symbols from that module that
it uses. Each listed symbol reports the number of modules using it\n");
print "\nNOTE: Got $modversion_warnings CONFIG_MODVERSIONS warnings\n\n"
if $modversion_warnings;
print "~"x80 , "\n";
for my $thismod (sort keys %MODULE) {
my $list = $MODULE{$thismod};
my %depends;
$thismod =~ s/\.mod\.c/.ko/;
print "\t\t\t$thismod\n";
foreach my $symbol (@{$list}) {
my ($module, $value, undef, $gpl) = @{$SYMBOL{$symbol}};
push (@{$depends{"$module"}}, "$symbol $value");
}
print_depends_on(\%depends);
}
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