#Quick cpu linux how to#
#Quick cpu linux install#
#Quick cpu linux update#

Sample output: itlb_multihit l1tf mds meltdown spec_store_bypass spectre_v1 spectre_v2 tsx_async_abortĪnd. $ ls /sys/devices/system/cpu/vulnerabilities/ > STATUS: VULNERABLE (PTI is needed to mitigate the vulnerability)Īlternatively, you can check Spectre/Meltdown vulnerabilities like below. > STATUS: VULNERABLE (IBRS+IBPB or retpoline+IBPB is needed to mitigate the vulnerability) > STATUS: VULNERABLE (Vulnerable: _user pointer sanitization and usercopy barriers only no swapgs barriers) You should see a message something like below.

#Quick cpu linux install#

On Fedora: $ sudo dnf install $ sudo apt install spectre-meltdown-checkerĪfter installing spectre-meltdown-checker, run it as root user or with sudo privileges to check if Spectre and Meltdown mitigations are turnd off: On CentOS, RHEL: $ sudo yum install epel-release $ sudo yum install spectre-meltdown-checker On Debian, Ubuntu: $ sudo apt install spectre-meltdown-checker It is available in the official repositories of some Linux distributions. We can use 'spectre-meltdown-checker' tool that helps you to identify the Spectre and Meltdown vulnerabilities in Linux. Check if Spectre/Meltdown mitigations are disabled This will boost your system's performance a little bit, but it may also expose users to several CPU vulnerabilities. We have now disabled all Spectre and Meltdown mitigations.

In some Linux systems, you might need to add these Kernel parameters in 'GRUB_CMDLINE_LINUX_DEFAULT='.'.

#Quick cpu linux update#

And then update GRUB configuration using command: $ sudo grub2-mkconfig On RPM-based systems like CentOS and RHEL, edit /etc/sysconfig/grub file: $ sudo /etc/sysconfig/grubĪdd the above parameters in GRUB_CMDLINE_LINUX.

mitigations=off - Disable all mitigations.įor more details about each flag, do a quick google search.Īfter adding the Kernel parameter(s), update the GRUB configuration using command: $ sudo update-grubįinally, reboot the system: $ sudo reboot.

tsx_async_abort=off - Disable TAA (TSX Async Abort) mitigation.

tsx=on - Enable Intel's TSX (Transactional Synchronization Extensions) support.

mds=off - Control mitigation for the Micro-architectural Data Sampling (MDS) vulnerability.

no_stf_barrier - Disable Store-forwarding barrier (PPC only).

nospec_store_bypass_disable - Disable all mitigations for the Speculative Store Bypass vulnerability.

It also drops the swap size and available RAM limit restriction on both hypervisor and bare metal. Disables hypervisor mitigations and doesn't emit any warnings. The kernel PTE inversion protection is unconditionally enabled and cannot be disabled.

l1tf=off - Control mitigation of the L1TF vulnerability on affected CPUs.

With this option data leaks are possible in the system.

nospectre_v1 - Disable mitigations for Spectre Variant 1 (bounds check bypass).

System may allow data leaks with this option, which is equivalent to spectre_v2=off.

nospectre_v2 - Disable all mitigations for the Spectre variant 2 (indirect branch prediction) vulnerability.

Disabling this feature removes hardening, but improves performance of system calls and interrupts. Control Page Table Isolation of user and kernel address spaces.

noibpb - Disable Indirect Branch Prediction Barriers.

noibrs - Disable Indirect Branch Restricted Speculation in the microcode.

These are the Kernel parameters that you can use for disabling all the Spectre/Meltdown mitigations that are slowing down your Linux system. Kernel parameters for disabling all the Spectre and Meltdown mitigations Unless you clearly know what you are doing, don't do this. This will disable all Spectre and Meltdown mitigations on Intel CPUs and leave your Linux systems wide open to all security risks. A word of cautionīefore implementing the following solution, I must warn you - THIS IS HIGHLY INSECURE and NOT RECOMMENDED.

#Quick cpu linux how to#

This brief guide explains how to make Linux system to run faster on Intel CPUs by turning off the Spectre and Meltdown mitigations. If you are confident that your systems are well-protected and want every ounce of performance that you can get out of your personal system, this guide is for you. Yes, the mitigations will cause a performance hit. Even though the security patches helps to mitigate the vulnerabilities, they also have impacted the system's performance as well. In the recent Kernel versions, the patches are implemented by default. Thankfully, the Kernel developers have released security patches to address the Meltdown/Spectre issues. You probably have heard about Meltdown and Spectre vulnerabilities that affected many modern processors, including certain processors by Intel, AMD, System Z, Power and ARM.