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-rw-r--r--Documentation/sysctl/kernel.txt16
-rw-r--r--Documentation/sysctl/net.txt11
-rw-r--r--Documentation/sysctl/vm.txt19
3 files changed, 36 insertions, 10 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 57653a44b128..daabdd7ee543 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -60,6 +60,7 @@ show up in /proc/sys/kernel:
- panic_on_warn
- perf_cpu_time_max_percent
- perf_event_paranoid
+- perf_event_max_stack
- pid_max
- powersave-nap [ PPC only ]
- printk
@@ -645,7 +646,7 @@ allowed to execute.
perf_event_paranoid:
Controls use of the performance events system by unprivileged
-users (without CAP_SYS_ADMIN). The default value is 1.
+users (without CAP_SYS_ADMIN). The default value is 2.
-1: Allow use of (almost) all events by all users
>=0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
@@ -654,6 +655,19 @@ users (without CAP_SYS_ADMIN). The default value is 1.
==============================================================
+perf_event_max_stack:
+
+Controls maximum number of stack frames to copy for (attr.sample_type &
+PERF_SAMPLE_CALLCHAIN) configured events, for instance, when using
+'perf record -g' or 'perf trace --call-graph fp'.
+
+This can only be done when no events are in use that have callchains
+enabled, otherwise writing to this file will return -EBUSY.
+
+The default value is 127.
+
+==============================================================
+
pid_max:
PID allocation wrap value. When the kernel's next PID value
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
index 809ab6efcc74..f0480f7ea740 100644
--- a/Documentation/sysctl/net.txt
+++ b/Documentation/sysctl/net.txt
@@ -43,6 +43,17 @@ Values :
1 - enable the JIT
2 - enable the JIT and ask the compiler to emit traces on kernel log.
+bpf_jit_harden
+--------------
+
+This enables hardening for the Berkeley Packet Filter Just in Time compiler.
+Supported are eBPF JIT backends. Enabling hardening trades off performance,
+but can mitigate JIT spraying.
+Values :
+ 0 - disable JIT hardening (default value)
+ 1 - enable JIT hardening for unprivileged users only
+ 2 - enable JIT hardening for all users
+
dev_weight
--------------
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index cb0368459da3..34a5fece3121 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -581,15 +581,16 @@ Specify "[Nn]ode" for node order
"Zone Order" orders the zonelists by zone type, then by node within each
zone. Specify "[Zz]one" for zone order.
-Specify "[Dd]efault" to request automatic configuration. Autoconfiguration
-will select "node" order in following case.
-(1) if the DMA zone does not exist or
-(2) if the DMA zone comprises greater than 50% of the available memory or
-(3) if any node's DMA zone comprises greater than 70% of its local memory and
- the amount of local memory is big enough.
-
-Otherwise, "zone" order will be selected. Default order is recommended unless
-this is causing problems for your system/application.
+Specify "[Dd]efault" to request automatic configuration.
+
+On 32-bit, the Normal zone needs to be preserved for allocations accessible
+by the kernel, so "zone" order will be selected.
+
+On 64-bit, devices that require DMA32/DMA are relatively rare, so "node"
+order will be selected.
+
+Default order is recommended unless this is causing problems for your
+system/application.
==============================================================