"内核污染"是什么意思？

Question

我的操作系统是Fedora 17.最近,内核污染警告"kernel/auditsc.c:1772上的内核错误!-abrt"发生:不应报告此问题(这可能是一个已知问题).发生内核问题,但内核已被污染(flags:GD).内核维护者无法诊断受污染的报告.

然后,我得到以下内容:

# cat /proc/sys/kernel/tainted
128

# dmesg | grep -i taint
[ 8306.955523] Pid: 4511, comm: chrome Tainted: G      D      3.9.10-100.fc17.i686.PAE #1 Dell Inc. 
[ 8307.366310] Pid: 4571, comm: chrome Tainted: G      D      3.9.10-100.fc17.i686.PAE #1 Dell Inc. 

似乎值"128"非常严重:128 - 系统已经死亡.

这个警告怎么样？由于chrome被标记为"受污染"的来源,任何人都会遇到这个问题？

Answer 1

为了(过度)简化,"污染"意味着内核处于一种状态之外的状态,如果它是从开源源新建的并以预期的方式使用的话.这是一种标记内核以警告人们(例如,开发人员)可能存在未知原因使其不可靠的方式,并且调试它可能是困难的或不可能的.

在这种情况下,'GD'表示所有模块都被许可为GPL或兼容(即非专有),并且发生了崩溃或BUG().

原因如下:

请参阅:oops-tracing.txt

---------------------------------------------------------------------------
Tainted kernels:

Some oops reports contain the string 'Tainted: ' after the program
counter. This indicates that the kernel has been tainted by some
mechanism.  The string is followed by a series of position-sensitive
characters, each representing a particular tainted value.

  1: 'G' if all modules loaded have a GPL or compatible license, 'P' if
     any proprietary module has been loaded.  Modules without a
     MODULE_LICENSE or with a MODULE_LICENSE that is not recognised by
     insmod as GPL compatible are assumed to be proprietary.

  2: 'F' if any module was force loaded by "insmod -f", ' ' if all
     modules were loaded normally.

  3: 'S' if the oops occurred on an SMP kernel running on hardware that
     hasn't been certified as safe to run multiprocessor.
     Currently this occurs only on various Athlons that are not
     SMP capable.

  4: 'R' if a module was force unloaded by "rmmod -f", ' ' if all
     modules were unloaded normally.

  5: 'M' if any processor has reported a Machine Check Exception,
     ' ' if no Machine Check Exceptions have occurred.

  6: 'B' if a page-release function has found a bad page reference or
     some unexpected page flags.

  7: 'U' if a user or user application specifically requested that the
     Tainted flag be set, ' ' otherwise.

  8: 'D' if the kernel has died recently, i.e. there was an OOPS or BUG.

  9: 'A' if the ACPI table has been overridden.

 10: 'W' if a warning has previously been issued by the kernel.
     (Though some warnings may set more specific taint flags.)

 11: 'C' if a staging driver has been loaded.

 12: 'I' if the kernel is working around a severe bug in the platform
     firmware (BIOS or similar).

 13: 'O' if an externally-built ("out-of-tree") module has been loaded.

 14: 'E' if an unsigned module has been loaded in a kernel supporting
     module signature.

 15: 'L' if a soft lockup has previously occurred on the system.

 16: 'K' if the kernel has been live patched.

The primary reason for the 'Tainted: ' string is to tell kernel
debuggers if this is a clean kernel or if anything unusual has
occurred.  Tainting is permanent: even if an offending module is
unloaded, the tainted value remains to indicate that the kernel is not
trustworthy.