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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333;background:white">Hi there,</span><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333"><br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333;background:white">I would like to implement a command , to be able to disable all variants(or at least the ones causing performance impact). As per the RH article: </span><a href="https://access.redhat.com/articles/3311301," title="Follow link"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#3B73AF;background:white;text-decoration:none">https://access.redhat.com/articles/3311301,</span></a><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333;background:white"> we
would be able to only disable spectre variant 2 and 3(pti). <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333;background:white">I need an option to disable variant 1, 3a and 4 as well. Some of the recent articles suggest that options like no_spectre_v1, no_spectre_v2 and
spec_store_bypass_disable parameters are available in latest versions of kernel(4.15 and above). </span><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333"><br>
<br>
</span><a href="https://www.zdnet.com/article/linux-kernel-gets-another-option-to-disable-spectre-mitigations/" title="Follow link"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#3B73AF;background:white;text-decoration:none">https://www.zdnet.com/article/linux-kernel-gets-another-option-to-disable-spectre-mitigations/</span></a><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333;background:white"> </span><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333"><br>
</span><a href="https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html?highlight=kernel%20parameters" title="Follow link"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#3B73AF;background:white;text-decoration:none">https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html?highlight=kernel%20parameters</span></a><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333;background:white"> </span><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333"><br>
<br>
<span style="background:white">Can this be made available in our Centos 7 kernels? Or is there any plan for RH to implement the same in any future release?<o:p></o:p></span></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<o:p></o:p></p>
<p class="MsoNormal">Nupur<o:p></o:p></p>
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