kernel メッセージのTaintedについて

kernelのメッセージが出た時にいつもNot taintedって出てましたが、このまえ、初めて、Taintedって出ていたのでメモしました。

これまでは、以下のようなNot taintedってメッセージ。Notって書いてあったのであまり気にしていませんでした。

Apr 22 16:48:27 dev001 kernel: Pid: 2429, comm: perl Not tainted 2.6.32-431.el6.x86_64 #1

それがこんな感じのメッセージ出ていたのでちょっとびっくり。

(Tainted: G        W  -- ------------   )

調べてみたところ、フラグの意味は以下のような感じみたいです。

/**
 *      print_tainted - return a string to represent the kernel taint state.
 *
 *  'P' - Proprietary module has been loaded.
 *  'F' - Module has been forcibly loaded.
 *  'S' - SMP with CPUs not designed for SMP.
 *  'R' - User forced a module unload.
 *  'M' - System experienced a machine check exception.
 *  'B' - System has hit bad_page.
 *  'U' - Userspace-defined naughtiness.
 *  'D' - Kernel has oopsed before
 *  'A' - ACPI table overridden.
 *  'W' - Taint on warning.
 *  'C' - modules from drivers/staging are loaded.
 *  'I' - Working around severe firmware bug.
 *  'O' - Out-of-tree module has been loaded.
 *  'E' - Unsigned module has been loaded.
 *  'L' - A soft lockup has previously occurred.
 *  'K' - Kernel has been live patched.
 *
 *      The string is overwritten by the next call to print_tainted().
 */

http://askubuntu.com/questions/248470/what-does-the-kernel-taint-value-mean

あと、procからtaintedのstatusも確認できました。何もなければ、0なのですが、warningが出ている状態だと、512が返ってきていました。

cat /proc/sys/kernel/tainted

statusの意味は以下のとおり。

tainted:

Non-zero if the kernel has been tainted.  Numeric values, which
can be ORed together:

   1 - A module with a non-GPL license has been loaded, this
       includes modules with no license.
       Set by modutils >= 2.4.9 and module-init-tools.
   2 - A module was force loaded by insmod -f.
       Set by modutils >= 2.4.9 and module-init-tools.
   4 - Unsafe SMP processors: SMP with CPUs not designed for SMP.
   8 - A module was forcibly unloaded from the system by rmmod -f.
  16 - A hardware machine check error occurred on the system.
  32 - A bad page was discovered on the system.
  64 - The user has asked that the system be marked "tainted".  This
       could be because they are running software that directly modifies
       the hardware, or for other reasons.
 128 - The system has died.
 256 - The ACPI DSDT has been overridden with one supplied by the user
        instead of using the one provided by the hardware.
 512 - A kernel warning has occurred.
1024 - A module from drivers/staging was loaded.
2048 - The system is working around a severe firmware bug.
4096 - An out-of-tree module has been loaded.
8192 - An unsigned module has been loaded in a kernel supporting module
       signature.
16384 - A soft lockup has previously occurred on the system.
32768 - The kernel has been live patched.

https://www.kernel.org/doc/Documentation/sysctl/kernel.txt

taintedという響きから嫌だなぁと思っていましたが、同じtaintedでも中身によって掘り下げれそうですね。