Non-zero if the kernel has been tainted. Numeric values, which can be ORed together. The letters are seen in “Tainted” line of Oops reports.
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1 `(P)` proprietary module was loaded
2 `(F)` module was force loaded
4 `(S)` kernel running on an out of specification system
8 `(R)` module was force unloaded
16 `(M)` processor reported a Machine Check Exception (MCE)
32 `(B)` bad page referenced or some unexpected page flags
64 `(U)` taint requested by userspace application
128 `(D)` kernel died recently, i.e. there was an OOPS or BUG
256 `(A)` an ACPI table was overridden by user
512 `(W)` kernel issued warning
1024 `(C)` staging driver was loaded
2048 `(I)` workaround for bug in platform firmware applied
4096 `(O)` externally-built ("out-of-tree") module was loaded
8192 `(E)` unsigned module was loaded
16384 `(L)` soft lockup occurred
32768 `(K)` kernel has been live patched
65536 `(X)` Auxiliary taint, defined and used by for distros
131072 `(T)` The kernel was built with the struct randomization plugin
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See Documentation/admin-guide/tainted-kernels.rst for more information.
Note: writes to this sysctl interface will fail with EINVAL if the kernel is booted with the command line option panic_on_taint=<bitmask>,nousertaint and any of the ORed together values being written to tainted match with the bitmask declared on panic_on_taint. See Documentation/admin-guide/kernel-parameters.rst for more details on that particular kernel command line option and its optional nousertaint switch.