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Peter Anvin" , Ingo Molnar , Joao Martins , Jonathan Corbet , Konrad Rzeszutek Wilk , Paolo Bonzini , Sean Christopherson , Thomas Gleixner , David Woodhouse , Greg Kroah-Hartman , Juergen Gross , Peter Zijlstra , Tony Luck , Babu Moger , Tom Lendacky , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] x86/speculation: Support Automatic IBRS Message-ID: References: <20221104213651.141057-1-kim.phillips@amd.com> <20221104213651.141057-3-kim.phillips@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20221104213651.141057-3-kim.phillips@amd.com> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 04, 2022 at 04:36:50PM -0500, Kim Phillips wrote: > - Allow for spectre_v2=autoibrs in the kernel command line, > reverting to auto-selection if the feature isn't available. Why? What the whole logic here should do is enable autoibrs when detected automatically, without the need for the user to even select it as it is the superior mitigation. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette