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 $debug = 0;
  26 GetOptions(@common_options,
  27         "debug" => \$debug) or pod2usage(1);
  28
  29 pod2usage(1) if($help || scalar(@ARGV) != 1);
  30
  31 my $file = abs_path($ARGV[0]);
  32
  33 my $tmpdir = tempdir('ksplice-tmp-XXXXXX', TMPDIR => 1, CLEANUP => 1);
  34 chdir($tmpdir);
  35 my $ksplice = unpack_update($file);
  36 chdir($ksplice);
  37
  38 my $nounload = runstr("lsmod") =~ m/- $/m;
  39
  40 (my $kid = $ksplice) =~s|ksplice[-_]([^-_]+)|$1|;
  41 my $update = "ksplice_$kid";
  42 if(update_loaded($kid)) {
  43         my $stage = get_stage($kid);
  44         if ($stage eq "applied") {
  45                 print STDERR "Ksplice update $kid already applied.\n";
  46                 exit(0);
  47         }
  48         die "Reversed Ksplice module $update already loaded!" if ($stage eq "reversed");
  49 }
  50
  51 runstr_err(qw(modprobe -q ksplice)) eq "" || die;
  52 if (-e "ksplice-$kid.ko") {
  53         if (runstr("lsmod") =~ m/^ksplice_$kid\s+/) {
  54                 die "Ksplice core module ksplice_$kid already loaded.";
  55         }
  56         if (!load_module("ksplice-$kid.ko", "debug=$debug")) {
  57                 die "Error loading Ksplice core for update $kid";
  58         }
  59 }
  60
  61 foreach my $helper (glob('ksplice-*-helper.ko')) {
  62         (my $primary = $helper) =~ s/\-helper\.ko$/.ko/;
  63         die unless(-e $primary && -e $helper);
  64         (my $target = $primary) =~ s/^ksplice-[^_]+_(.*)\.ko/$1/;
  65         if ($target ne 'vmlinux' && runstr("lsmod") !~ m/^${target}\s/m) {
  66                 cleanup_modules();
  67                 die "Module $target to be patched not loaded";
  68         }
  69 }
  70 foreach my $helper (glob('ksplice-*-helper.ko')) {
  71         (my $primary = $helper) =~ s/\-helper\.ko$/.ko/;
  72         if(!load_module($primary)) {
  73                 die "Error loading primary module $primary";
  74         }
  75         if(!load_module($helper)) {
  76                 my ($debugfile, $debugout) = get_debug_output("init_$kid");
  77                 print STDERR "Error loading helper module $helper\n";
  78                 (my $module = $primary) =~ s/-/_/g;
  79                 $module =~ s/\.ko//;
  80                 cleanup_modules();
  81                 if(defined $debugfile) {
  82                         print $debugout;
  83                         print("Debugging output saved to $debugfile\n");
  84                 }
  85                 die;
  86         }
  87 }
  88
  89 set_debug_level($kid, $debug);
  90 set_stage($kid, "applied");
  91 my $stage = get_stage($kid);
  92 if($stage ne 'applied') {
  93         my ($debugfile, $debugout) = get_debug_output($kid);
  94         my $abort_cause = get_abort_cause($kid);
  95         my $conflicts = get_conflicts($kid);
  96         cleanup_modules();
  97         print STDERR "Error applying Ksplice update $kid:\n";
  98         print $debugout;
  99         print_error($abort_cause);
 100         if ($abort_cause eq 'code_busy') {
 101                 print $conflicts;
 102         }
 103         print("Debugging output saved to $debugfile\n");
 104         die;
 105 }
 106 mkpath("/var/run/ksplice/updates/$kid");
 107 copy("patch", "/var/run/ksplice/updates/$kid/patch");
 108 foreach my $helper (glob('ksplice-*-helper.ko')) {
 109         $helper =~ s/-/_/g;
 110         $helper =~ s/\.ko$//;
 111         runval('rmmod', $helper) if(!$nounload);
 112 }
 113 print "Done!\n";
 114 exit(0);
 115
 116 my @modules_loaded = qw();
 117
 118 sub load_module {
 119         my ($module, @params) = @_;
 120         if (runval_raw("insmod", $module, @params) != 0) {
 121                 child_error();
 122                 return 0;
 123         }
 124         $module =~ s/\.ko//;
 125         $module =~ s/-/_/g;
 126         push @modules_loaded, $module;
 127         return 1;
 128 }
 129
 130 sub cleanup_modules {
 131         foreach my $module (reverse(@modules_loaded)) {
 132                 runval("rmmod", $module) if(!$nounload);
 133         }
 134 }
 135
 136 sub print_error {
 137         my ($error) = @_;
 138         my %errors = (
 139                 "no_match" => <<'END',
 140 Ksplice has aborted the upgrade because Ksplice has been unable to match the
 141 object code produced by your current compiler and assembler against the running
 142 kernel's object code.  If you provided the exact kernel source to the running
 143 kernel, then it appears that your current compiler and/or assembler are
 144 behaving differently from the compiler and assembler used to build the running
 145 kernel.  If possible, please use the exact compiler and assembler that were
 146 used to build the running kernel.  If you are using exactly the same compiler
 147 and assembler, consider reporting a bug to PACKAGE_BUGREPORT.
 148 END
 149                 "code_busy" => <<'END',
 150 Ksplice has aborted the upgrade because it appears that the code that you are
 151 trying to patch is continuously in use by the system.  More specifically,
 152 Ksplice has been unable to find a moment when one or more of the to-be-patched
 153 functions is not on a thread's kernel stack.
 154 END
 155                 "bad_system_map" => <<'END',
 156 Ksplice has aborted the upgrade because it appears that the System.map file
 157 provided to ksplice-create does not match the running kernel.
 158 END
 159                 "failed_to_find" => <<'END',
 160 Ksplice has aborted the upgrade because it was unable to resolve some of the
 161 symbols used in the update.
 162 END
 163                 "already_reversed" => <<'END',
 164 The Ksplice update that you are attempting to apply has already been applied
 165 and reversed.  You need to unload the Ksplice modules associated with this
 166 update before you can apply this update again.
 167 END
 168                 "missing_export" => <<'END',
 169 Ksplice has aborted the upgrade because the symbols exported by the kernel
 170 did not match Ksplice's expectations.
 171 END
 172                 "unexpected_running_task" => <<'END',
 173 Ksplice has aborted the upgrade because of an unexpected failure during the
 174 kernel stack check.  Please consider reporting a bug to PACKAGE_BUGREPORT.
 175 END
 176                 "out_of_memory" => <<'END',
 177 Ksplice has aborted the upgrade because the kernel ran out of memory.
 178 END
 179                 "unexpected" => <<'END',
 180 Ksplice has aborted because of an unexpected error.
 181 Please consider reporting a bug to PACKAGE_BUGREPORT.
 182 END
 183                 "UNKNOWN" => <<'END',
 184 The Ksplice kernel component has returned an error code that this version of
 185 ksplice-apply does not understand.
 186 END
 187                 "ok" => <<'END',
 188 Ksplice has aborted the upgrade for unknown reasons.
 189 Please consider reporting a bug to PACKAGE_BUGREPORT.
 190 END
 191         );
 192         $error = "UNKNOWN" if (!exists $errors{$error});
 193         print STDERR "\n$errors{$error}\n";
 194 }
 195
 196 =head1 NAME
 197
 198 ksplice-apply - Apply an on-disk Ksplice update to the running kernel
 199
 200 =head1 SYNOPSIS
 201
 202 B<ksplice-apply> I<UPDATE_TARBALL>
 203
 204 =head1 DESCRIPTION
 205
 206 B<ksplice-apply> takes as input a Ksplice update tarball, as generated by
 207 L<ksplice-create(8)>, and it applies the update to the running binary kernel.
 208
 209 The update tarball used with B<ksplice-apply> must have been generated for the
 210 running kernel's version.
 211
 212 =head1 OPTIONS
 213
 214 =over 8
 215
 216 =item B<--debug>
 217
 218 Applies the update with debugging output enabled.  Recommended only for
 219 debugging.
 220
 221 =back
 222
 223 =head1 SEE ALSO
 224
 225 L<ksplice-create(8)>, L<ksplice-view(8)>, L<ksplice-undo(8)>
 226
 227 =head1 COPYRIGHT
 228
 229 Copyright (C) 2007-2008  Jeffrey Brian Arnold <jbarnold@mit.edu>
 230 Copyright (C) 2008  Anders Kaseorg <andersk@mit.edu>,
 231                     Tim Abbott <tabbott@mit.edu>
 232
 233 This is free software and documentation.  You can redistribute and/or modify it
 234 under the terms of the GNU General Public License, version 2.
 235
 236 =cut