Lines Matching +full:no +full:- +full:unaligned +full:- +full:direct +full:- +full:access
5 .. See scripts/check-sysctl-docs to keep this up to date
13 Documentation/admin-guide/sysctl/index.rst.
15 ------------------------------------------------------------------------------
39 If BSD-style process accounting is enabled these values control
71 The machine hardware name, the same output as ``uname -m``
77 This variable has no effect and may be removed in future kernel
129 Ctrl-Alt-Delete). Writing a value to this file which doesn't
130 correspond to a running process will result in ``-ESRCH``.
132 See also `ctrl-alt-del`_.
210 captured in parallel, but that no waiting will take place (i.e. the
211 collecting process is not guaranteed access to ``/proc/<crashing
237 ctrl-alt-del
240 When the value in this file is 0, ctrl-alt-del is trapped and
248 mode, the ctrl-alt-del is intercepted by the program before it
259 When ``dmesg_restrict`` is set to 0 there are no restrictions.
293 See Documentation/driver-api/firmware/fallback-mechanisms.rst.
347 debug information. If enabled, arch-specific all-CPU stack dumping
367 See Documentation/admin-guide/lockup-watchdogs.rst for more information.
379 modern systems rely exclusively on the netlink-based uevent source and
393 1: Will non-maskably interrupt all CPUs and dump their backtraces when
432 0 means infinite timeout, no checking is done.
456 When this value reaches 0, no more warnings will be reported.
459 -1: report an infinite number of warnings.
465 Controls whether the panic kmsg data should be reported to Hyper-V.
473 ignore-unaligned-usertrap
476 On architectures where unaligned accesses cause traps, and where this
479 unaligned traps are logged.
482 0 Log all unaligned accesses.
487 See also `unaligned-trap`_.
499 -EPERM) for unprivileged processes not in the io_uring_group group.
503 always fails with -EPERM. Existing io_uring instances can still be
513 to create an io_uring instance. If io_uring_group is set to -1 (the
525 Once true, kexec can no longer be used, and the toggle cannot be set
541 -1 Unlimited calls to kexec. This is the default setting.
570 The correct long-term solution is to do the permission checks at
591 This sysctl only affects module autoloading. It has no effect on the
646 By default they are equal to -1, which means generic allocation logic.
652 2) Toggle with non-default value will be set back to -1 by kernel after
654 fails, it is undefined if the value remains unmodified or is reset to -1.
678 that are programmed to generate Non-Maskable Interrupts (NMIs) periodically
687 Documentation/admin-guide/kernel-parameters.rst).
698 A value of 0 means no change. The default value is 200 meaning the NMI
706 balancing. Memory is moved automatically to nodes that access it often.
724 ideally is offset by improved memory locality but there is no universal
738 promotion throughput. The per-node max promotion throughput in MB/s
739 will be limited to be no more than the set value.
756 1: Will non-maskably interrupt all CPUs and dump their backtraces when
786 The only way to tune these values is to rebuild the kernel :-)
792 if your architecture did not always support 32-bit UIDs (i.e. arm,
794 applications that use the old 16-bit UID/GID system calls, if the
838 1 Panic immediately. If the `panic` sysctl is also non-zero then the
938 When ``panic_on_rcu_stall`` is set to 0, this value is has no effect.
956 sampling rate no matter how CPU time it takes.
958 1-100 Attempt to throttle perf's sample rate to this
974 For backward compatibility reasons access to system performance
981 -1 Allow use of (almost) all events by all users.
989 Disallow raw tracepoint access by users without ``CAP_PERFMON``.
991 >=1 Disallow CPU event access by users without ``CAP_PERFMON``.
1002 '``perf record -g``' or '``perf trace --call-graph fp``'.
1004 This can only be done when no events are in use that have callchains
1005 enabled, otherwise writing to this file will return ``-EBUSY``.
1013 Control size of per-cpu ring buffer not counted against mlock limit.
1023 instance, when using '``perf record -g``' or '``perf trace --call-graph fp``'.
1025 This can only be done when no events are in use that have callchains
1026 enabled, otherwise writing to this file will return ``-EBUSY``.
1034 Controls user space access for reading perf event counters.
1037 The default value is 0 (access disabled).
1045 When set to 0, user space access is disabled.
1048 registers through perf, any direct access without perf intervention will trigger
1051 When set to 2, which enables legacy mode (user space has direct access to cycle
1073 powersave-nap (PPC only)
1076 If set, Linux-PPC will use the 'nap' mode of powersaving,
1109 Value from 0 - 10000 is allowed.
1146 a one-time setting until next reboot: once set, it cannot be changed by
1175 writable for compatibility purposes, but writing to it has no effect
1181 writing to it has no effect on any RNG behavior.
1198 loaded to random addresses. Also for PIE-linked binaries, the
1208 start of the brk area is randomized. There are however no known
1209 non-legacy applications that would be broken this way, so for most
1218 real-root-dev
1221 See Documentation/admin-guide/initrd.rst.
1224 reboot-cmd (SPARC only)
1240 this value to 0. On Non-EAS platforms, write operation fails and
1247 Documentation/accounting/delay-accounting.rst. Enabling this feature incurs
1316 See Documentation/userspace-api/seccomp_filter.rst.
1319 sg-big-buff
1379 feature will do you no good unless you also configure your resource
1394 -1 Legacy per-write sysctl value handling, with no printk warnings.
1460 On x86, each "split lock" imposes a system-wide performance penalty. On larger
1462 denials of service to well-behaved and potentially more important users.
1473 0 Disable the mitigation mode - just warns the split lock on kernel log
1475 1 Enable the mitigation mode (this is the default) - penalizes the split
1498 stop-a (SPARC only)
1501 Controls Stop-A:
1504 0 Stop-A has no effect.
1505 1 Stop-A breaks to the PROM (default).
1508 Stop-A is always enabled on a panic, so that the user can return to
1515 See Documentation/admin-guide/sysrq.rst.
1521 Non-zero if the kernel has been tainted. Numeric values, which can be
1537 4096 `(O)` externally-built ("out-of-tree") module was loaded
1545 See Documentation/admin-guide/tainted-kernels.rst for more information.
1552 See Documentation/admin-guide/kernel-parameters.rst for more details on
1556 threads-max
1566 The minimum value that can be written to ``threads-max`` is 1.
1568 The maximum value that can be written to ``threads-max`` is given by the
1571 If a value outside of this range is written to ``threads-max`` an
1577 When set to a non-zero value, attempt to migrate timers away from idle cpus to
1605 See Documentation/admin-guide/kernel-parameters.rst and
1606 Documentation/trace/boottime-trace.rst.
1609 unaligned-trap
1612 On architectures where unaligned accesses cause traps, and where this
1614 ``arc``, ``parisc`` and ``loongarch``), controls whether unaligned traps
1618 0 Do not emulate unaligned accesses.
1619 1 Emulate unaligned accesses. This is the default setting.
1622 See also `ignore-unaligned-usertrap`_.
1629 value is non-zero, unknown NMI is trapped and then panic occurs. At
1641 will return ``-EPERM``. Once set to 1, this can't be cleared from the
1700 to re-enable cores that by default were not running the watchdog,
1707 echo 0,2-4 > /proc/sys/kernel/watchdog_cpumask