On Fri, Jan 26, 2018 at 09:19:09AM -0800, Linus Torvalds wrote: > But did we do that "disable stuffing with SMEP"? I'm not seeing it. In > my tree, it's only conditional on X86_FEATURE_RETPOLINE. Or rather, enable stuffing on !SMEP: + if ((!boot_cpu_has(X86_FEATURE_PTI) && + !boot_cpu_has(X86_FEATURE_SMEP)) || is_skylake_era()) { + setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW); + pr_info("Filling RSB on context switch\n"); + } Should be c995efd5a740 ("x86/retpoline: Fill RSB on context switch for affected CPUs") in your tree. -- Regards/Gruss, Boris. SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) --