From 9eece400c626655b826d5b1b4933e65af3073ab8 Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Thu, 15 Jul 2021 09:40:02 +0200 Subject: [PATCH] x86/cpuid: Fix HLE and RTM handling (again) MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit For reasons which are my fault, but I don't recall why, the FDP_EXCP_ONLY/NO_FPU_SEL adjustment uses the whole special_features[] array element, not the two relevant bits. HLE and RTM were recently added to the list of special features, causing them to be always set in guest view, irrespective of the toolstacks choice on the matter. Rewrite the logic to refer to the features specifically, rather than relying on the contents of the special_features[] array. Fixes: 8fe24090d9 ("x86/cpuid: Rework HLE and RTM handling") Reported-by: Edwin Török Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich master commit: 60fa12dbf1d4d2c4ffe1ef34b495b24aa7e41aa0 master date: 2021-06-07 15:43:35 +0100 --- xen/arch/x86/cpuid.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/cpuid.c b/xen/arch/x86/cpuid.c index 27132f91a6..18bb0faf34 100644 --- a/xen/arch/x86/cpuid.c +++ b/xen/arch/x86/cpuid.c @@ -563,9 +563,11 @@ void recalculate_cpuid_policy(struct domain *d) sanitise_featureset(fs); /* Fold host's FDP_EXCP_ONLY and NO_FPU_SEL into guest's view. */ - fs[FEATURESET_7b0] &= ~special_features[FEATURESET_7b0]; + fs[FEATURESET_7b0] &= ~(cpufeat_mask(X86_FEATURE_FDP_EXCP_ONLY) | + cpufeat_mask(X86_FEATURE_NO_FPU_SEL)); fs[FEATURESET_7b0] |= (host_cpuid_policy.feat._7b0 & - special_features[FEATURESET_7b0]); + (cpufeat_mask(X86_FEATURE_FDP_EXCP_ONLY) | + cpufeat_mask(X86_FEATURE_NO_FPU_SEL))); cpuid_featureset_to_policy(fs, p); -- 2.39.5