Messages in this thread |  | | Date | Fri, 26 Jan 2018 18:27:12 +0100 | From | Borislav Petkov <> | Subject | Re: [RFC 09/10] x86/enter: Create macros to restrict/unrestrict Indirect Branch Speculation |
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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) --
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