ksplice-apply.in

   1 #!/usr/bin/perl
   2
   3 # Copyright (C) 2007-2009  Ksplice, Inc.
   4 # Authors: Jeff Arnold, Anders Kaseorg, Tim Abbott
   5 #
   6 # This program is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License, version 2.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program; if not, write to the Free Software
  16 # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
  17 # 02110-1301, USA.
  18
  19 use strict;
  20 use warnings;
  21 use sigtrap 'handler', \&handler, qw(normal-signals error-signals);
  22 use lib 'KSPLICE_DATA_DIR';
  23 use Ksplice;
  24
  25 my $debug;
  26 my $debugon = 0;
  27 my $partial = 0;
  28 GetOptions(@common_options,
  29         "partial" => \$partial,
  30         "debug" => \$debugon,
  31         "debugfile=s" => \$debug) or pod2usage(1);
  32
  33 pod2usage(1) if($help || scalar(@ARGV) != 1);
  34
  35 my $file = abs_path($ARGV[0]);
  36 $debugon = 1 if(defined $debug);
  37 $debug = abs_path($debug) if (defined $debug);
  38
  39 my $tmpdir = tempdir('ksplice-tmp-XXXXXX', TMPDIR => 1, CLEANUP => 1);
  40 chdir($tmpdir);
  41 my $ksplice = unpack_update($file);
  42 chdir($ksplice);
  43
  44 die "No contents file in $file\n" if (!-e "contents");
  45 open(CONTENTS, '<', "contents");
  46 my $core;
  47 my @changes;
  48 while (<CONTENTS>) {
  49         my ($type, @args) = split(' ', $_);
  50         if ($type eq 'core') {
  51                 die "Multiple core modules in $file!" if (defined $core);
  52                 $core = {};
  53                 @$core{qw(module file)} = @args;
  54         } elsif ($type eq 'change') {
  55                 my $change = {};
  56                 @$change{qw(target new_code new_code_file old_code old_code_file)} = @args;
  57                 push @changes, $change;
  58         }
  59 }
  60 close(CONTENTS);
  61
  62 die "Update was built using an old version of Ksplice" if (@changes == 0);
  63
  64 my $nounload = runstr("lsmod") =~ m/- $/m;
  65
  66 (my $kid = $ksplice) =~s|ksplice[-_]([^-_]+)|$1|;
  67 my $update = "ksplice_$kid";
  68 if(update_loaded($kid)) {
  69         my $stage = get_stage($kid);
  70         if ($stage eq "applied") {
  71                 print STDERR "Ksplice update $kid already applied.\n";
  72                 exit(0);
  73         }
  74         die "Reversed Ksplice module $update already loaded!" if ($stage eq "reversed");
  75 }
  76
  77 runstr_err(qw(modprobe -q ksplice)) eq "" || die;
  78 if (defined $core) {
  79         die "Could not find Ksplice core module $core->{file}\n" if (!-e $core->{file});
  80         if (runstr("lsmod") =~ m/^\Q$core->{module}\E\s+/) {
  81                 die "Ksplice core module $core already loaded.";
  82         }
  83         if (!load_module($core->{file}, "debug=$debugon")) {
  84                 die "Error loading Ksplice core module $core->{module} for update $kid";
  85         }
  86 }
  87
  88 foreach my $change (@changes) {
  89         die unless (-e $change->{old_code_file} && -e $change->{new_code_file});
  90         if ($change->{'target'} ne 'vmlinux' &&
  91             runstr("lsmod") !~ m/^\Q$change->{target}\E\s+/m) {
  92                 if (!$partial) {
  93                         cleanup_modules();
  94                         print_error("target_not_loaded");
  95                         die "Module $change->{target} to be patched not loaded";
  96                 }
  97         }
  98 }
  99
 100 foreach my $change (@changes) {
 101         if(!load_module($change->{new_code_file})) {
 102                 die "Error loading new code module $change->{new_code}";
 103         }
 104         if(!load_module($change->{old_code_file})) {
 105                 my $debugfile = get_debug_output("init_$kid", $debug);
 106                 print STDERR "Error loading old code module $change->{old_code}\n";
 107                 cleanup_modules();
 108                 if($debugon && defined $debugfile) {
 109                         print("Debugging output saved to $debugfile\n");
 110                 }
 111                 die;
 112         }
 113 }
 114
 115 mkpath("/var/run/ksplice/updates/$kid");
 116 copy("patch", "/var/run/ksplice/updates/$kid/patch") if (-e "patch");
 117 copy("description", "/var/run/ksplice/updates/$kid/description") if (-e "description");
 118
 119 set_debug_level($kid, $debugon);
 120 set_partial($kid, $partial);
 121 set_stage($kid, "applied");
 122 my $stage = get_stage($kid);
 123 if($stage ne 'applied') {
 124         my $debugfile = get_debug_output($kid, $debug);
 125         my $abort_cause = get_abort_cause($kid);
 126         my $conflicts = get_conflicts($kid);
 127         rmtree("/var/run/ksplice/updates/$kid") if (-e "/var/run/ksplice/updates/$kid");
 128         cleanup_modules();
 129         print STDERR "Error applying Ksplice update $kid:\n";
 130         print_error($abort_cause);
 131         if ($abort_cause eq 'code_busy') {
 132                 print $conflicts;
 133         }
 134         if ($debugon && defined $debugfile) {
 135                 print("Debugging output saved to $debugfile\n");
 136         }
 137         die;
 138 }
 139
 140 if (!$nounload) {
 141         foreach my $change (@changes) {
 142                 runval('rmmod', $change->{old_code});
 143                 runval('rmmod', $change->{new_code}) if ($partial && refcount($change->{new_code}) == 0);
 144         }
 145 }
 146
 147 print "Done!\n";
 148 exit(0);
 149
 150 my @modules_loaded = qw();
 151
 152 sub handler {
 153         my ($sig) = @_;
 154         die "caught SIG$sig, abort\n" if (!defined($kid));
 155         die "caught SIG$sig after finished\n"
 156             if (update_loaded($kid) && (get_stage($kid) eq 'applied'));
 157         print STDERR "caught SIG$sig, aborting\n";
 158         rmtree("/var/run/ksplice/updates/$kid") if (-e "/var/run/ksplice/updates/$kid");
 159         cleanup_modules();
 160         exit(1);
 161 }
 162
 163 sub load_module {
 164         my ($module, @params) = @_;
 165         push @modules_loaded, ($module =~ m/^(.*)\.ko$/);
 166         if (runval_raw("insmod", $module, @params) != 0) {
 167                 pop @modules_loaded;
 168                 child_error();
 169                 return 0;
 170         }
 171         return 1;
 172 }
 173
 174 sub refcount {
 175         my ($module) = @_;
 176         $module =~ s/-/_/g;
 177         foreach(split(/\n/, runstr("lsmod"))) {
 178                 if (m/^(\S+)\s+[0-9]+\s+([0-9])+\s/) {
 179                         return $2 if ($1 eq $module);
 180                 }
 181         }
 182         return -1;
 183 }
 184
 185 sub cleanup_modules {
 186         foreach my $module (reverse(@modules_loaded)) {
 187                 runval_raw("rmmod", $module) if(!$nounload);
 188         }
 189 }
 190
 191 sub print_error {
 192         my ($error) = @_;
 193         my %errors = (
 194                 "no_match" => <<'END',
 195 Ksplice has aborted the upgrade because Ksplice has been unable to match the
 196 object code produced by your current compiler and assembler against the running
 197 kernel's object code.  If you provided the exact kernel source to the running
 198 kernel, then it appears that your current compiler and/or assembler are
 199 behaving differently from the compiler and assembler used to build the running
 200 kernel.  If possible, please use the exact compiler and assembler that were
 201 used to build the running kernel.  If you are using exactly the same compiler
 202 and assembler, consider reporting a bug to PACKAGE_BUGREPORT.
 203 END
 204                 "code_busy" => <<'END',
 205 Ksplice has aborted the upgrade because it appears that the code that you are
 206 trying to patch is continuously in use by the system.  More specifically,
 207 Ksplice has been unable to find a moment when one or more of the to-be-patched
 208 functions is not on a thread's kernel stack.
 209 END
 210                 "bad_system_map" => <<'END',
 211 Ksplice has aborted the upgrade because it appears that the System.map file
 212 provided to ksplice-create does not match the running kernel.
 213 END
 214                 "failed_to_find" => <<'END',
 215 Ksplice has aborted the upgrade because it was unable to resolve some of the
 216 symbols used in the update.
 217 END
 218                 "already_reversed" => <<'END',
 219 The Ksplice update that you are attempting to apply has already been applied
 220 and reversed.  You need to unload the Ksplice modules associated with this
 221 update before you can apply this update again.
 222 END
 223                 "missing_export" => <<'END',
 224 Ksplice has aborted the upgrade because the symbols exported by the kernel
 225 did not match Ksplice's expectations.
 226 END
 227                 "unexpected_running_task" => <<'END',
 228 Ksplice has aborted the upgrade because of an unexpected failure during the
 229 kernel stack check.  Please consider reporting a bug to PACKAGE_BUGREPORT.
 230 END
 231                 "target_not_loaded" => <<'END',
 232 Ksplice has aborted the upgrade because one of the modules to be
 233 patched by the update was not loaded.  If you want to apply this
 234 update only to those modules that are loaded, then you should use the
 235 --partial option.
 236 END
 237                 "out_of_memory" => <<'END',
 238 Ksplice has aborted the upgrade because the kernel ran out of memory.
 239 END
 240                 "call_failed" => <<'END',
 241 Ksplice has aborted the upgrade at the request of a one of the
 242 pre-application hooks that were included as part of this Ksplice
 243 update.  This is likely the result of a bug in the patch used to
 244 generate this update.
 245 END
 246                 "unexpected" => <<'END',
 247 Ksplice has aborted because of an unexpected error.
 248 Please consider reporting a bug to PACKAGE_BUGREPORT.
 249 END
 250                 "UNKNOWN" => <<'END',
 251 The Ksplice kernel component has returned an error code that this version of
 252 ksplice-apply does not understand.
 253 END
 254                 "ok" => <<'END',
 255 Ksplice has aborted the upgrade for unknown reasons.
 256 Please consider reporting a bug to PACKAGE_BUGREPORT.
 257 END
 258         );
 259         $error = "UNKNOWN" if (!exists $errors{$error});
 260         print STDERR "\n$errors{$error}\n";
 261 }
 262
 263 =head1 NAME
 264
 265 ksplice-apply - Apply an on-disk Ksplice update to the running kernel
 266
 267 =head1 SYNOPSIS
 268
 269 B<ksplice-apply> [I<OPTIONS>] I<UPDATE_TARBALL>
 270
 271 =head1 DESCRIPTION
 272
 273 B<ksplice-apply> takes as input a Ksplice update tarball, as generated by
 274 L<ksplice-create(8)>, and it applies the update to the running binary kernel.
 275
 276 The update tarball used with B<ksplice-apply> must have been generated for the
 277 running kernel's version.
 278
 279 =head1 OPTIONS
 280
 281 =over 8
 282
 283 =item B<--debug>
 284
 285 Applies the update with debugging output enabled.  Recommended only for
 286 debugging.
 287
 288 =item B<--debugfile=>I<filename>
 289
 290 Sets the location where debugging output should be saved.  Implies --debug.
 291
 292 =item B<--partial>
 293
 294 Applies the update only to those modules which are loaded.  Any
 295 modules patched by the update that are not loaded are ignored (without
 296 this option, Ksplice aborts if any modules patched by the update are
 297 not loaded).
 298
 299 =back
 300
 301 =head1 SEE ALSO
 302
 303 L<ksplice-create(8)>, L<ksplice-view(8)>, L<ksplice-undo(8)>
 304
 305 =head1 BUGS
 306
 307 Please report bugs to <PACKAGE_BUGREPORT>.
 308
 309 =head1 AUTHORS
 310
 311 Jeff Arnold, Anders Kaseorg, and Tim Abbott
 312
 313 =head1 COPYRIGHT
 314
 315 Copyright (C) 2007-2009  Ksplice, Inc.
 316
 317 This is free software and documentation.  You can redistribute and/or modify it
 318 under the terms of the GNU General Public License, version 2.
 319
 320 =cut