Re-enabling CPU’s by writing to /sys/devices/system/cpu/cpuX/online will crash the RHEL 5 system.
Issue
-
If the CPUs are disabled by writing to
/sys/devices/system/cpu/cpuX/online, kernel panic may be observed. -
So far, this has been observed on virtual servers only.
Environment
-
Observed on VMWare guest servers.
-
Possibly, it may be observed on KVM as well.
-
Observed on RHEL 5.11 kernel version
2.6.18-434.el5.
Subscriber exclusive content
A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.