diff options
Diffstat (limited to 'Documentation/sysctl/kernel.txt')
| -rw-r--r-- | Documentation/sysctl/kernel.txt | 47 |
1 files changed, 45 insertions, 2 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index eded671d55eb..1b8775298cf7 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -38,7 +38,9 @@ show up in /proc/sys/kernel: - hung_task_panic - hung_task_check_count - hung_task_timeout_secs +- hung_task_check_interval_secs - hung_task_warnings +- hyperv_record_panic_msg - kexec_load_disabled - kptr_restrict - l2cr [ PPC only ] @@ -87,6 +89,7 @@ show up in /proc/sys/kernel: - shmmni - softlockup_all_cpu_backtrace - soft_watchdog +- stack_erasing - stop-a [ SPARC only ] - sysrq ==> Documentation/admin-guide/sysrq.rst - sysctl_writes_strict @@ -354,7 +357,7 @@ This file shows up if CONFIG_DETECT_HUNG_TASK is enabled. hung_task_timeout_secs: -Check interval. When a task in D state did not get scheduled +When a task in D state did not get scheduled for more than this value report a warning. This file shows up if CONFIG_DETECT_HUNG_TASK is enabled. @@ -363,6 +366,18 @@ Possible values to set are in range {0..LONG_MAX/HZ}. ============================================================== +hung_task_check_interval_secs: + +Hung task check interval. If hung task checking is enabled +(see hung_task_timeout_secs), the check is done every +hung_task_check_interval_secs seconds. +This file shows up if CONFIG_DETECT_HUNG_TASK is enabled. + +0 (default): means use hung_task_timeout_secs as checking interval. +Possible values to set are in range {0..LONG_MAX/HZ}. + +============================================================== + hung_task_warnings: The maximum number of warnings to report. During a check interval @@ -374,6 +389,16 @@ This file shows up if CONFIG_DETECT_HUNG_TASK is enabled. ============================================================== +hyperv_record_panic_msg: + +Controls whether the panic kmsg data should be reported to Hyper-V. + +0: do not report panic kmsg data. + +1: report the panic kmsg data. This is the default behavior. + +============================================================== + kexec_load_disabled: A toggle indicating if the kexec_load syscall has been disabled. This @@ -440,7 +465,8 @@ Notes: 1) kernel doesn't guarantee, that new object will have desired id. So, it's up to userspace, how to handle an object with "wrong" id. 2) Toggle with non-default value will be set back to -1 by kernel after -successful IPC object allocation. +successful IPC object allocation. If an IPC object allocation syscall +fails, it is undefined if the value remains unmodified or is reset to -1. ============================================================== @@ -962,6 +988,23 @@ detect a hard lockup condition. ============================================================== +stack_erasing + +This parameter can be used to control kernel stack erasing at the end +of syscalls for kernels built with CONFIG_GCC_PLUGIN_STACKLEAK. + +That erasing reduces the information which kernel stack leak bugs +can reveal and blocks some uninitialized stack variable attacks. +The tradeoff is the performance impact: on a single CPU system kernel +compilation sees a 1% slowdown, other systems and workloads may vary. + + 0: kernel stack erasing is disabled, STACKLEAK_METRICS are not updated. + + 1: kernel stack erasing is enabled (default), it is performed before + returning to the userspace at the end of syscalls. + +============================================================== + tainted: Non-zero if the kernel has been tainted. Numeric values, which can be |