Rip out the DebugSwap module param, as the sequence of events that led to its inclusion was one big mistake, the param no longer serves any purpose. Commit d1f85fbe836e ("KVM: SEV: Enable data breakpoints in SEV-ES") goofed by not adding a way for the userspace VMM to control the feature. Functionally, that was fine, but it broke attestation signatures because SEV_FEATURES are included in the signature. Commit 5abf6dceb066 ("SEV: disable SEV-ES DebugSwap by default") fixed that issue, but the underlying flaw of userspace not having a way to control SEV_FEATURES was still there. That flaw was addressed by commit 4f5defae7089 ("KVM: SEV: introduce KVM_SEV_INIT2 operation"), and so then 4dd5ecacb9a4 ("KVM: SEV: allow SEV-ES DebugSwap again") re-enabled DebugSwap by default. Now that the dust has settled, the module param doesn't serve any meaningful purpose. Cc: Tom Lendacky Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/sev.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index f59c65abe3cf..9b92f0cccfe6 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -53,9 +53,6 @@ module_param_named(sev_es, sev_es_enabled, bool, 0444); static bool sev_snp_enabled = true; module_param_named(sev_snp, sev_snp_enabled, bool, 0444); -/* enable/disable SEV-ES DebugSwap support */ -static bool sev_es_debug_swap_enabled = true; -module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444); static u64 sev_supported_vmsa_features; static unsigned int nr_ciphertext_hiding_asids; @@ -3150,12 +3147,10 @@ void __init sev_hardware_setup(void) sev_es_enabled = sev_es_supported; sev_snp_enabled = sev_snp_supported; - if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) || - !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) - sev_es_debug_swap_enabled = false; - sev_supported_vmsa_features = 0; - if (sev_es_debug_swap_enabled) + + if (sev_es_enabled && cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) && + cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) sev_supported_vmsa_features |= SVM_SEV_FEAT_DEBUG_SWAP; if (sev_snp_enabled && tsc_khz && cpu_feature_enabled(X86_FEATURE_SNP_SECURE_TSC)) -- 2.52.0.457.g6b5491de43-goog