Lines Matching +full:in +full:- +full:kernel
2 ---------------
4 The kernel will mark itself as 'tainted' when something occurs that might be
6 most of the time it's not a problem to run a tainted kernel; the information is
8 cause might be the event that got the kernel tainted. That's why bug reports
10 problems with an untainted kernel.
12 Note the kernel will remain tainted even after you undo what caused the taint
13 (i.e. unload a proprietary kernel module), to indicate the kernel remains not
14 trustworthy. That's also why the kernel will print the tainted state when it
15 notices an internal problem (a 'kernel bug'), a recoverable error
16 ('kernel oops') or a non-recoverable error ('kernel panic') and writes debug
18 check the tainted state at runtime through a file in ``/proc/``.
21 Tainted flag in bugs, oops or panics messages
24 You find the tainted state near the top in a line starting with 'CPU:'; if or
25 why the kernel was tainted is shown after the Process ID ('PID:') and a shortened
28 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
30 CPU: 0 PID: 4424 Comm: insmod Tainted: P W O 4.20.0-0.rc6.fc30 #1
35 You'll find a 'Not tainted: ' there if the kernel was not tainted at the
37 either letters or blanks. In above example it looks like this::
41 The meaning of those characters is explained in the table below. In this case
42 the kernel got tainted earlier because a proprietary Module (``P``) was loaded,
43 a warning occurred (``W``), and an externally-built module was loaded (``O``).
51 ``cat /proc/sys/kernel/tainted``. If that returns ``0``, the kernel is not
53 decode that number is the script ``tools/debugging/kernel-chktaint``, which your
54 distribution might ship as part of a package called ``linux-tools`` or
55 ``kernel-tools``; if it doesn't you can download the script from
56 `git.kernel.org <https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/plain/tools/deb…
57 and execute it with ``sh kernel-chktaint``, which would print something like
58 this on the machine that had the statements in the logs that were quoted earlier::
60 Kernel is Tainted for following reasons:
62 * Kernel issued warning (#9)
63 * Externally-built ('out-of-tree') module was loaded (#12)
64 See Documentation/admin-guide/tainted-kernels.rst in the Linux kernel or
65 https://www.kernel.org/doc/html/latest/admin-guide/tainted-kernels.html for
70 reason that got your kernel tainted, as in this case you can find the number
77 $ for i in $(seq 18); do echo $(($i-1)) $(($(cat /proc/sys/kernel/tainted)>>($i-1)&1));done
83 Bit Log Number Reason that got the kernel tainted
87 2 _/S 4 kernel running on an out of specification system
92 7 _/D 128 kernel died recently, i.e. there was an OOPS or BUG
94 9 _/W 512 kernel issued warning
96 11 _/I 2048 workaround for bug in platform firmware applied
97 12 _/O 4096 externally-built ("out-of-tree") module was loaded
100 15 _/K 32768 kernel has been live patched
102 17 _/T 131072 kernel was built with the struct randomization plugin
103 18 _/N 262144 an in-kernel test has been run
106 Note: The character ``_`` is representing a blank in this table to make reading
117 1) ``F`` if any module was force loaded by ``insmod -f``, ``' '`` if all
120 2) ``S`` if the kernel is running on a processor or system that is out of
123 Kernel will be tainted if, for example:
125 - on x86: PAE is forced through forcepae on intel CPUs (such as Pentium M)
127 kernel is running on non officially capable SMP Athlon CPUs, MSRs are
129 - on arm: kernel running on certain CPUs (such as Keystone 2) without
130 having certain kernel features enabled.
131 - on arm64: there are mismatched hardware features between CPUs, the
132 bootloader has booted CPUs in different modes.
133 - certain drivers are being used on non supported architectures (such as
136 irqchip/irq-gic on arm64 ...).
137 - x86/x86_64: Microcode late loading is dangerous and will result in
138 tainting the kernel. It requires that all CPUs rendezvous to make sure
144 3) ``R`` if a module was force unloaded by ``rmmod -f``, ``' '`` if all
150 5) ``B`` If a page-release function has found a bad page reference or some
151 unexpected page flags. This indicates a hardware problem or a kernel bug;
152 there should be other information in the log indicating why this tainting
158 7) ``D`` if the kernel has died recently, i.e. there was an OOPS or BUG.
162 9) ``W`` if a warning has previously been issued by the kernel.
167 11) ``I`` if the kernel is working around a severe bug in the platform
170 12) ``O`` if an externally-built ("out-of-tree") module has been loaded.
172 13) ``E`` if an unsigned module has been loaded in a kernel supporting
177 15) ``K`` if the kernel has been live patched.
181 17) ``T`` Kernel was build with the randstruct plugin, which can intentionally
182 produce extremely unusual kernel structure layouts (even performance