Messages in this thread | | | From | Jon Masters <> | Subject | Re: [PATCH 2/2] x86/speculation: Provide application property based STIBP protection | Date | Tue, 2 Oct 2018 11:41:28 -0400 |
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On 9/19/18 5:35 PM, Tim Chen wrote: > This patch provides an application property based spectre_v2 > protection with STIBP against attack from another app from > a sibling hyper-thread. For security sensitive non-dumpable > app, STIBP will be turned on before switching to it for Intel > processors vulnerable to spectre_v2.
A general comment. I think in practice this will be similar to the speculative store buffer bypass (aka "variant 4") issue in terms of opt-in mitigation. Many users won't want to take the performance hit of having STIBP by default for peer threads. We should make sure that we don't force users into a mitigation but retain an option. Whether it's default-on or not can be debated, though I think the vendors lean toward having default-off with an opt-in, and customers will probably agree. So anyway, I encourage a pragmatic approach similar to that for SSBD.
Jon.
-- Computer Architect | Sent with my Fedora powered laptop
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