From 0102c8c7fdfc4bd700971daff2b94470f4eafae4 Mon Sep 17 00:00:00 2001 From: Dapeng Mi Date: Thu, 17 Sep 2026 09:52:33 +0800 Subject: perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rsp DMR introduces Offmodule Response events in place of the legacy Offcore Response events, but it still exposes the inherited offcore_rsp PMU attribute for programming the corresponding MSR data. Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface matches the underlying event name and avoids user & tooling confusion. Signed-off-by: Dapeng Mi Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com --- .../admin-guide/namespaces/resource-control.rst | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) create mode 100644 Documentation/admin-guide/namespaces/resource-control.rst (limited to 'Documentation/admin-guide/namespaces/resource-control.rst') diff --git a/Documentation/admin-guide/namespaces/resource-control.rst b/Documentation/admin-guide/namespaces/resource-control.rst new file mode 100644 index 000000000..553a44803 --- /dev/null +++ b/Documentation/admin-guide/namespaces/resource-control.rst @@ -0,0 +1,18 @@ +==================================== +User namespaces and resource control +==================================== + +The kernel contains many kinds of objects that either don't have +individual limits or that have limits which are ineffective when +a set of processes is allowed to switch their UID. On a system +where the admins don't trust their users or their users' programs, +user namespaces expose the system to potential misuse of resources. + +In order to mitigate this, we recommend that admins enable memory +control groups on any system that enables user namespaces. +Furthermore, we recommend that admins configure the memory control +groups to limit the maximum memory usable by any untrusted user. + +Memory control groups can be configured by installing the libcgroup +package present on most distros editing /etc/cgrules.conf, +/etc/cgconfig.conf and setting up libpam-cgroup. -- cgit v1.3.1