[systemd-bugs] [Bug 78478] New: Please add CPU and memory hotplug udev rules

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=78478

          Priority: medium
            Bug ID: 78478
          Assignee: systemd-bugs at lists.freedesktop.org
           Summary: Please add CPU and memory hotplug udev rules
        QA Contact: systemd-bugs at lists.freedesktop.org
          Severity: normal
    Classification: Unclassified
                OS: All
          Reporter: benjamin.drung at profitbricks.com
          Hardware: Other
            Status: NEW
           Version: unspecified
         Component: general
           Product: systemd

Hi,

please add udev rules to enable hotplugged CPUs and memory. I propose following
two rules:

ACTION=="add", SUBSYSTEM=="cpu", ATTR{online}=="0", ATTR{online}="1"
ACTION=="add", SUBSYSTEM=="memory", ATTR{state}=="offline",
ATTR{state}="online"

These rules are tested (without the ATTR online/state checks) on Debian
7/testing, Fedora 19/20/21, and Ubuntu 12.04/13.10/14.04.

Some distributions already ship CPU and memory hotplug rules. openSUSE 13.1 has
80-hotplug-cpu-mem.rules:

SUBSYSTEM=="cpu", ACTION=="add", TEST=="online", ATTR{online}=="0",
ATTR{online}="1"
SUBSYSTEM=="memory", ACTION=="add", TEST=="state", ATTR{state}=="offline",
ATTR{state}="online"

CentOS 6 modified the acpi_memhotplug kernel module to automatically online
memory (configurable with CONFIG_ACPI_HOTPLUG_MEMORY_AUTO_ONLINE). This patch
is not mainlined (yet). They ship one rule for CPU hotplugging in
/lib/udev/rules.d/40-redhat.rules:

ACTION=="add", KERNEL=="cpu[0-9]*", RUN+="/bin/bash -c 'echo 1 >
/sys/devices/system/cpu/%k/online'"

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/systemd-bugs/attachments/20140509/e95da594/attachment.html>