RHEL7: kernel commandline parameters are ignored if any invalid parameter is encoutered.

Solution Verified - Updated -

Issue

  • RHEL7: kernel commandline parameters are ignored if any invalid parameter is encoutered.
  • We have isolated CPU in the boot configuration, and same is confirmed from the /proc/cmdline. However we do not see isolated cpus in /sys/devices/system/cpu
Kernel command line: BOOT_IMAGE=/vmlinuz-3.10.0-1160.el7.x86_64 root=/dev/mapper/rhel_dhcp130--155-root ro crashkernel=auto spectre_v2=retpoline rd.lvm.lv=rhel_dhcp130-155/root rd.lvm.lv=rhel_dhcp130-155/swap rhgb quiet LANG=en_US.UTF-8 selinux=0 elevator=deadline printk.time=2 intel_idle.max_cstat=0 processor.max_cstat=0 idle=poll mce=off nohz=off isolcpus=1-2 rcu_nocbs=2-23 rcu_nocb_poll nopti numa_balancing=disable rcutree.kthread_prio=3 skew_tick=1 intel_pstat=disabe mitigations=off

# cat /sys/devices/system/cpu/isolated
<nothing>

Environment

  • Red Hat Enterprise Linux 7.

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.

Current Customers and Partners

Log in for full access

Log In

New to Red Hat?

Learn more about Red Hat subscriptions

Using a Red Hat product through a public cloud?

How to access this content