ksplice-apply.in

   1 #!/usr/bin/perl
   2
   3 # Copyright (C) 2007-2008  Jeffrey Brian Arnold <jbarnold@mit.edu>
   4 # Copyright (C) 2008  Anders Kaseorg <andersk@mit.edu>,
   5 #                     Tim Abbott <tabbott@mit.edu>
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License, version 2.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program; if not, write to the Free Software
  17 # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
  18 # 02110-1301, USA.
  19
  20 use strict;
  21 use warnings;
  22 use lib 'KSPLICE_DATA_DIR';
  23 use Ksplice;
  24
  25 my $debug = 0;
  26 my $partial = 0;
  27 GetOptions(@common_options,
  28         "partial" => \$partial,
  29         "debug" => \$debug) or pod2usage(1);
  30
  31 pod2usage(1) if($help || scalar(@ARGV) != 1);
  32
  33 my $file = abs_path($ARGV[0]);
  34
  35 my $tmpdir = tempdir('ksplice-tmp-XXXXXX', TMPDIR => 1, CLEANUP => 1);
  36 chdir($tmpdir);
  37 my $ksplice = unpack_update($file);
  38 chdir($ksplice);
  39
  40 die "No contents file in $file\n" if (!-e "contents");
  41 open(CONTENTS, '<', "contents");
  42 my $core;
  43 while (<CONTENTS>) {
  44         my @line = split(' ', $_);
  45         if ($line[0] eq 'core') {
  46                 die "Multiple core modules in $file!" if (defined $core);
  47                 $core = {
  48                         module => $line[1],
  49                         file => $line[2],
  50                 };
  51         }
  52 }
  53 close(CONTENTS);
  54
  55 my $nounload = runstr("lsmod") =~ m/- $/m;
  56
  57 (my $kid = $ksplice) =~s|ksplice[-_]([^-_]+)|$1|;
  58 my $update = "ksplice_$kid";
  59 if(update_loaded($kid)) {
  60         my $stage = get_stage($kid);
  61         if ($stage eq "applied") {
  62                 print STDERR "Ksplice update $kid already applied.\n";
  63                 exit(0);
  64         }
  65         die "Reversed Ksplice module $update already loaded!" if ($stage eq "reversed");
  66 }
  67
  68 runstr_err(qw(modprobe -q ksplice)) eq "" || die;
  69 if (defined $core) {
  70         die "Could not find Ksplice core module $core->{file}\n" if (!-e $core->{file});
  71         if (runstr("lsmod") =~ m/^\Q$core->{module}\E\s+/) {
  72                 die "Ksplice core module $core already loaded.";
  73         }
  74         if (!load_module($core->{file}, "debug=$debug")) {
  75                 die "Error loading Ksplice core module $core->{module} for update $kid";
  76         }
  77 }
  78
  79 my @helpers = ();
  80 foreach my $helper (glob('ksplice-*-helper.ko')) {
  81         (my $primary = $helper) =~ s/\-helper\.ko$/.ko/;
  82         die unless(-e $primary && -e $helper);
  83         (my $target = $primary) =~ s/^ksplice-[^_]+_(.*)\.ko/$1/;
  84         if ($target ne 'vmlinux' && runstr("lsmod") !~ m/^${target}\s/m) {
  85                 if (!$partial) {
  86                         cleanup_modules();
  87                         print_error("target_not_loaded");
  88                         die "Module $target to be patched not loaded";
  89                 }
  90         }
  91         push @helpers, $helper;
  92 }
  93 foreach my $helper (@helpers) {
  94         (my $primary = $helper) =~ s/\-helper\.ko$/.ko/;
  95         if(!load_module($primary)) {
  96                 die "Error loading primary module $primary";
  97         }
  98         if(!load_module($helper)) {
  99                 my ($debugfile, $debugout) = get_debug_output("init_$kid");
 100                 print STDERR "Error loading helper module $helper\n";
 101                 (my $module = $primary) =~ s/-/_/g;
 102                 $module =~ s/\.ko//;
 103                 cleanup_modules();
 104                 if($debug && defined $debugfile) {
 105                         print $debugout;
 106                         print("Debugging output saved to $debugfile\n");
 107                 }
 108                 die;
 109         }
 110 }
 111
 112 set_debug_level($kid, $debug);
 113 set_partial($kid, $partial);
 114 set_stage($kid, "applied");
 115 my $stage = get_stage($kid);
 116 if($stage ne 'applied') {
 117         my ($debugfile, $debugout) = get_debug_output($kid);
 118         my $abort_cause = get_abort_cause($kid);
 119         my $conflicts = get_conflicts($kid);
 120         cleanup_modules();
 121         print STDERR "Error applying Ksplice update $kid:\n";
 122         print $debugout if (defined $debugfile);
 123         print_error($abort_cause);
 124         if ($abort_cause eq 'code_busy') {
 125                 print $conflicts;
 126         }
 127         if ($debug && defined $debugfile) {
 128                 print("Debugging output saved to $debugfile\n");
 129         }
 130         die;
 131 }
 132 mkpath("/var/run/ksplice/updates/$kid");
 133 copy("patch", "/var/run/ksplice/updates/$kid/patch") if (-e "patch");
 134 copy("description", "/var/run/ksplice/updates/$kid/description") if (-e "description");
 135 if (!$nounload) {
 136         foreach my $helper (@helpers) {
 137                 $helper =~ s/-/_/g;
 138                 $helper =~ s/\.ko$//;
 139                 (my $primary = $helper) =~ s/_helper$//;
 140                 runval('rmmod', $helper);
 141                 runval('rmmod', $primary) if ($partial && refcount($primary) == 0);
 142         }
 143 }
 144 print "Done!\n";
 145 exit(0);
 146
 147 my @modules_loaded = qw();
 148
 149 sub load_module {
 150         my ($module, @params) = @_;
 151         if (runval_raw("insmod", $module, @params) != 0) {
 152                 child_error();
 153                 return 0;
 154         }
 155         $module =~ s/\.ko//;
 156         $module =~ s/-/_/g;
 157         push @modules_loaded, $module;
 158         return 1;
 159 }
 160
 161 sub refcount {
 162         my ($module) = @_;
 163         foreach(split(/\n/, runstr("lsmod"))) {
 164                 if (m/^(\S+)\s+[0-9]+\s+([0-9])+\s/) {
 165                         return $2 if ($1 eq $module);
 166                 }
 167         }
 168         return -1;
 169 }
 170
 171 sub cleanup_modules {
 172         foreach my $module (reverse(@modules_loaded)) {
 173                 runval("rmmod", $module) if(!$nounload);
 174         }
 175 }
 176
 177 sub print_error {
 178         my ($error) = @_;
 179         my %errors = (
 180                 "no_match" => <<'END',
 181 Ksplice has aborted the upgrade because Ksplice has been unable to match the
 182 object code produced by your current compiler and assembler against the running
 183 kernel's object code.  If you provided the exact kernel source to the running
 184 kernel, then it appears that your current compiler and/or assembler are
 185 behaving differently from the compiler and assembler used to build the running
 186 kernel.  If possible, please use the exact compiler and assembler that were
 187 used to build the running kernel.  If you are using exactly the same compiler
 188 and assembler, consider reporting a bug to PACKAGE_BUGREPORT.
 189 END
 190                 "code_busy" => <<'END',
 191 Ksplice has aborted the upgrade because it appears that the code that you are
 192 trying to patch is continuously in use by the system.  More specifically,
 193 Ksplice has been unable to find a moment when one or more of the to-be-patched
 194 functions is not on a thread's kernel stack.
 195 END
 196                 "bad_system_map" => <<'END',
 197 Ksplice has aborted the upgrade because it appears that the System.map file
 198 provided to ksplice-create does not match the running kernel.
 199 END
 200                 "failed_to_find" => <<'END',
 201 Ksplice has aborted the upgrade because it was unable to resolve some of the
 202 symbols used in the update.
 203 END
 204                 "already_reversed" => <<'END',
 205 The Ksplice update that you are attempting to apply has already been applied
 206 and reversed.  You need to unload the Ksplice modules associated with this
 207 update before you can apply this update again.
 208 END
 209                 "missing_export" => <<'END',
 210 Ksplice has aborted the upgrade because the symbols exported by the kernel
 211 did not match Ksplice's expectations.
 212 END
 213                 "unexpected_running_task" => <<'END',
 214 Ksplice has aborted the upgrade because of an unexpected failure during the
 215 kernel stack check.  Please consider reporting a bug to PACKAGE_BUGREPORT.
 216 END
 217                 "target_not_loaded" => <<'END',
 218 Ksplice has aborted the upgrade because one of the modules to be
 219 patched by the update was not loaded.  If you want to apply this
 220 update only to those modules that are loaded, then you should use the
 221 --partial option.
 222 END
 223                 "out_of_memory" => <<'END',
 224 Ksplice has aborted the upgrade because the kernel ran out of memory.
 225 END
 226                 "call_failed" => <<'END',
 227 Ksplice has aborted the upgrade at the request of a one of the
 228 pre-application hooks that were included as part of this Ksplice
 229 update.  This is likely the result of a bug in the patch used to
 230 generate this update.
 231 END
 232                 "unexpected" => <<'END',
 233 Ksplice has aborted because of an unexpected error.
 234 Please consider reporting a bug to PACKAGE_BUGREPORT.
 235 END
 236                 "UNKNOWN" => <<'END',
 237 The Ksplice kernel component has returned an error code that this version of
 238 ksplice-apply does not understand.
 239 END
 240                 "ok" => <<'END',
 241 Ksplice has aborted the upgrade for unknown reasons.
 242 Please consider reporting a bug to PACKAGE_BUGREPORT.
 243 END
 244         );
 245         $error = "UNKNOWN" if (!exists $errors{$error});
 246         print STDERR "\n$errors{$error}\n";
 247 }
 248
 249 =head1 NAME
 250
 251 ksplice-apply - Apply an on-disk Ksplice update to the running kernel
 252
 253 =head1 SYNOPSIS
 254
 255 B<ksplice-apply> I<UPDATE_TARBALL>
 256
 257 =head1 DESCRIPTION
 258
 259 B<ksplice-apply> takes as input a Ksplice update tarball, as generated by
 260 L<ksplice-create(8)>, and it applies the update to the running binary kernel.
 261
 262 The update tarball used with B<ksplice-apply> must have been generated for the
 263 running kernel's version.
 264
 265 =head1 OPTIONS
 266
 267 =over 8
 268
 269 =item B<--debug>
 270
 271 Applies the update with debugging output enabled.  Recommended only for
 272 debugging.
 273
 274 =item B<--partial>
 275
 276 Applies the update only to those modules which are loaded.  Any
 277 modules patched by the update that are not loaded are ignored (without
 278 this option, Ksplice aborts if any modules patched by the update are
 279 not loaded).
 280
 281 =back
 282
 283 =head1 SEE ALSO
 284
 285 L<ksplice-create(8)>, L<ksplice-view(8)>, L<ksplice-undo(8)>
 286
 287 =head1 BUGS
 288
 289 Please report bugs to <PACKAGE_BUGREPORT>.
 290
 291 =head1 COPYRIGHT
 292
 293 Copyright (C) 2007-2008  Jeffrey Brian Arnold <jbarnold@mit.edu>
 294
 295 Copyright (C) 2008  Anders Kaseorg <andersk@mit.edu>,
 296                     Tim Abbott <tabbott@mit.edu>
 297
 298 This is free software and documentation.  You can redistribute and/or modify it
 299 under the terms of the GNU General Public License, version 2.
 300
 301 =cut