package/boot/kexec-tools/files/kdump.init

   1 #!/bin/sh /etc/rc.common
   2
   3 START=41
   4 STOP=90
   5
   6 BOOT_IMAGE=/boot/vmlinuz
   7
   8 EXTRA_COMMANDS="status"
   9 EXTRA_HELP="        status  Print crashkernel status"
  10
  11 verify_kdump() {
  12         local cfg="$1"
  13         local enabled
  14         local path
  15         local save_vmcore
  16         local save_dmesg
  17
  18         config_get_bool enabled "$cfg" enabled 1
  19         config_get_bool save_dmesg "$cfg" save_dmesg 1
  20         config_get_bool save_vmcore "$cfg" save_vmcore 0
  21
  22         [ "$enabled" -gt 0 ] || return 2
  23
  24         [ "$save_dmesg" -gt 0 ] || [ "$save_vmcore" -gt 0 ] || return 2
  25
  26         config_get path "$cfg" path "/"
  27
  28         [ -d "$path" ] || mkdir -p "$path" 2>/dev/null || return 1
  29 }
  30
  31 run_kdump() {
  32         local cfg="$1"
  33         local enabled
  34         local path
  35         local save_vmcore
  36         local save_dmesg
  37
  38         config_get_bool enabled "$cfg" enabled 1
  39         [ "$enabled" -gt 0 ] || return
  40
  41         config_get_bool save_dmesg "$cfg" save_dmesg 1
  42         config_get_bool save_vmcore "$cfg" save_vmcore 0
  43         config_get path "$cfg" path "/"
  44
  45         timestamp=$(date "+%Y%m%dT%H%M%S")
  46
  47         if [ "$save_vmcore" -eq 1 ]; then
  48                 echo -n "Saving vmcore (this may take a while)..."
  49                 # would like 'sparse' but busybox doesn't support it
  50                 dd if=/proc/vmcore of="$path/vmcore-$timestamp" conv=fsync bs=1M
  51                 echo " done"
  52         fi
  53
  54         if [ "$save_dmesg" -eq 1 ]; then
  55                 vmcore-dmesg /proc/vmcore > "$path/dmesg-$timestamp"
  56         fi
  57
  58         sync
  59         reboot -f
  60 }
  61
  62 find_kernel() {
  63         . /lib/functions.sh
  64         local kernel
  65
  66         kernel="$BOOT_IMAGE"
  67         if [ -r "$kernel" ]; then
  68                 echo $kernel
  69                 return 0
  70         fi
  71
  72         kernel="$(find_mtd_part kernel)"
  73         if [ -r "$kernel" ]; then
  74                 echo $kernel
  75                 return 0
  76         fi
  77
  78         for voldir in /sys/class/ubi/ubi*_*; do
  79                 [ ! -e "$voldir" ] && continue
  80                 if [ "$(cat "${voldir}/name")" = "kernel" ]; then
  81                         kernel="/dev/$(basename "$voldir")"
  82                         echo $kernel
  83                         return 0
  84                 fi
  85         done
  86
  87         return 1
  88 }
  89
  90 load_crashkernel() {
  91         local append_cmdline
  92         local kernel
  93
  94         kernel="$(find_kernel)"
  95         [ $? -gt 0 ] && return 1
  96
  97         case "$(uname -m)" in
  98                 i?86|x86_64)
  99                         grep -q "crashkernel=" /proc/cmdline || return 1
 100                         append_cmdline="1 irqpoll reset_devices maxcpus=1"
 101                         ;;
 102                 arm*)
 103                         append_cmdline="1 maxcpus=1 reset_devices"
 104                         ;;
 105         esac
 106         kexec -p "$kernel" --reuse-cmdline --append="$append_cmdline"
 107         return $?
 108 }
 109
 110 start() {
 111         local retval
 112
 113         if [ ! -e /sys/kernel/kexec_crash_loaded ]; then
 114                 return 1
 115         fi
 116
 117         if [ -e /proc/vmcore ]; then
 118                 config_load kdump
 119                 config_foreach run_kdump kdump
 120         else
 121                 config_load kdump
 122                 config_foreach verify_kdump kdump
 123                 retval=$?
 124                 [ $retval = 1 ] && return 1
 125                 [ $retval = 0 ] && load_crashkernel
 126                 return $?
 127         fi
 128 }
 129
 130 stop() {
 131         [ "$(cat /sys/kernel/kexec_crash_loaded)" = "1" ] || return
 132
 133         if [ -e "$BOOT_IMAGE" ]; then
 134                 kexec -p -u "$BOOT_IMAGE"
 135         fi
 136 }
 137
 138 status() {
 139         local retval kernel
 140
 141         if [ ! -e /sys/kernel/kexec_crash_loaded ]; then
 142                 echo "crashdump not supported by kernel"
 143                 return
 144         fi
 145
 146         if [ $(cat /sys/kernel/kexec_crash_size) -eq 0 ]; then
 147                 echo "memory for crashdump kernel not reserved!"
 148                 echo "check crashkernel= kernel cmdline parameter"
 149                 echo "(a reboot is required after installing kdump)"
 150                 return
 151         fi
 152
 153         kernel="$(find_kernel)"
 154         if [ $? -gt 0 ]; then
 155                 echo "cannot find kernel image"
 156                 return
 157         else
 158                 echo "using kernel image $kernel"
 159         fi
 160
 161         echo -n "kdump configuration is "
 162         config_load kdump
 163         retval=$?
 164         if [ $retval = 0 ]; then
 165                 if [ "$(config_foreach echo kdump)" ]; then
 166                         config_foreach verify_kdump kdump
 167                         retval=$?
 168                 else
 169                         retval=1
 170                 fi
 171         fi
 172
 173         if [ $retval = 0 ]; then
 174                 echo "valid"
 175         elif [ $retval = 2 ]; then
 176                 echo "disabled"
 177         else
 178                 echo "BROKEN"
 179         fi
 180
 181         echo -n "kexec crash kernel "
 182         if [ "$(cat /sys/kernel/kexec_crash_loaded)" = "0" ]; then
 183                 echo -n "not "
 184         fi
 185         echo "loaded"
 186 }