From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f70.google.com (mail-pj1-f70.google.com [209.85.216.70]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F2186447819 for ; Wed, 2 Sep 2026 23:09:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788390582; cv=none; b=jRM8a4WWAiMEegeJqRGVvoabeispI4vRh7S4h8iagr6yBR/S4ugUapsJ6SOAtNK9J+hkMk/AA0hM62vMRH4YPk5cBXKVN3zZTheJt9QvOsv75AvR03sHpk8c542Fk9jtOay2DD8G61NimmX5DaNxq7vNG7350waasgSYAEH+5Qk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788390582; c=relaxed/simple; bh=+1VgxsgnJQl02sR9ZTeNUA36gnlTtRp4JJQojJXfI0k=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=B+4YDNg1lZpo6Ao5anwaxKKmZHUYXrfZeon/CeEiXHeokT1DzDx4RYM94sm9aY7W3oYckTJTWcjfd21SubTjSP7etCwS4Zk3NBLJWyZwtKnyOIMVKYuMDqwR6mYTGDqZTHUEQIZyFFhB0NAl7W/mZt23lM0J8c9p8BwluR1EBW8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=bsDkvaXI; arc=none smtp.client-ip=209.85.216.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="bsDkvaXI" Received: by mail-pj1-f70.google.com with SMTP id 98e67ed59e1d1-38e1118e4abso3153736a91.0 for ; Wed, 02 Sep 2026 16:09:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788390577; x=1788995377; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:reply-to:from:to:cc:subject:date:message-id :reply-to:content-type; bh=Ry8TyeFFo2R/yg40KQakAe6hDAwm94Khs2os2DazZE0=; b=bsDkvaXID0M/xWoT88X9CwFb8J4u0GE5aLhdJ6FdfvN+qqRAGdx/5TfwN/XvdYIEk+ v68T9+mesS2M+opDfhjKOcxGx0NwNz4PWuyqmgDQmGp6ciQALZ4QzDT44wcvAqFA8a6T OxgYbqyGrOG5qXDL0UDr0bjwEbnHubjlI/OISHlsYeENjlFjTKuD049jxDGIzXvWOuOs ass6zJ6g6ZGbf5tuaLDIh/Ddugd9Xi0KqURrkqcojXVWvOsGLTa6AEptIRctw1MBII7I yZOOe4QbFvcxcJ+J2BJGW/vyElVQ3qVHib8RnqyO6ZsmP3o8t1T6zo2SOxUa5efix2Zr wy8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788390577; x=1788995377; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:reply-to:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to:content-type; bh=Ry8TyeFFo2R/yg40KQakAe6hDAwm94Khs2os2DazZE0=; b=Hws7RW87G/4nGuC3sVZlRlFPK4Ii0PGQA5QplllMhH56b526OI4N7+RRYs8KzBj43h EoqhtAEZEgJ6w3I4suIa53eUoTHaIU8vgkQrKwHrXENXUN0JJp75Pvq5KXviiTjUQ3tC Zi6zWZ+jX96AMEQayiEdi5kXxnimBP6Wgt3gD5MzWeXOhOl/1uqPuNK/m/WPxQS09qnv 70NtOXwSjB1y8mRoG86TvI/aOBKUrCkIOx8WJE6S1/h1o73V59GPsxT2sbiXNN6/Qo4A SD+87SWhOmUpeQZjFjSgvK2U6db1eIDFcPGDckVzepmZVgK9SdojfoXuddq1PCr8/uT3 gEJQ== X-Gm-Message-State: AFuF++kazYToO6tkZcuMWVp53U8i0ndvLGvY2TYCqD17nerX2Frg2Z9J GvD93NMk9Y9MtrjLtpoXhIFZpelKnZnGP2ruORaKxstpzStWeG6mv4EO8LsDd7BcbkiQux511Nt IGr2QNg== X-Received: from pjzd8.prod.google.com ([2002:a17:90a:e288:b0:398:d8f4:c3f6]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:2d85:b0:398:9c00:29f0 with SMTP id 98e67ed59e1d1-39aee249bd7mr12524431a91.24.1788390577209; Wed, 02 Sep 2026 16:09:37 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 2 Sep 2026 16:09:32 -0700 In-Reply-To: <20260902230932.2760127-1-seanjc@google.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260902230932.2760127-1-seanjc@google.com> X-Mailer: git-send-email 2.55.0.970.g62bdec98f9-goog Message-ID: <20260902230932.2760127-4-seanjc@google.com> Subject: [PATCH v3 3/3] KVM: VMX: Drop TDX_SHARED_BIT_PWL_{4,5} and dedup related code From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Rick Edgecombe , Xiaoyao Li , Kai Huang , Yan Zhao , Binbin Wu Content-Type: text/plain; charset="UTF-8" Fold the GPA => GFN conversion and bitshift logic for identifying the S-bit given the EPT root level into tdx_set_mirror_root_level() to dedup the math and drop TDX_SHARED_BIT_PWL_{4,5} in the process. In addition to deduping a small amount of code, using the level to compute the S-bit position more or less eliminates the risk of the mirror_root_level and gfn_direct_bits getting out of sync. Opportunistically switch the sanity check in tdx_load_mmu_pgd() to check the mirror root level, not the S-Bit location, now that it's all but impossible for the two things to get out of sync. For all intents and purposes, no functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/tdx.c | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index e6b7da616817..a0bc9f818f43 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -56,9 +56,6 @@ bool enable_tdx __ro_after_init; module_param_named(tdx, enable_tdx, bool, 0444); -#define TDX_SHARED_BIT_PWL_5 gpa_to_gfn(BIT_ULL(51)) -#define TDX_SHARED_BIT_PWL_4 gpa_to_gfn(BIT_ULL(47)) - static const struct tdx_sys_info *tdx_sysinfo; void tdh_vp_rd_failed(struct vcpu_tdx *tdx, char *uclass, u32 field, u64 err) @@ -1609,10 +1606,7 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu) void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level) { - u64 shared_bit = (pgd_level == 5) ? TDX_SHARED_BIT_PWL_5 : - TDX_SHARED_BIT_PWL_4; - - if (KVM_BUG_ON(shared_bit != kvm_gfn_direct_bits(vcpu->kvm), vcpu->kvm)) + if (KVM_BUG_ON(pgd_level != vcpu->kvm->arch.mirror_root_level, vcpu->kvm)) return; td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa); @@ -2765,6 +2759,7 @@ static __always_inline void tdx_set_mirror_root_level(struct kvm *kvm, int level BUILD_BUG_ON(level != 4 && level != 5); kvm->arch.mirror_root_level = level; + kvm->arch.gfn_direct_bits = gpa_to_gfn(BIT_ULL(level == 4 ? 47 : 51)); } static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd) @@ -2829,13 +2824,10 @@ static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd) kvm_tdx->attributes = td_params->attributes; kvm_tdx->xfam = td_params->xfam; - if (td_params->config_flags & TDX_CONFIG_FLAGS_MAX_GPAW) { - kvm->arch.gfn_direct_bits = TDX_SHARED_BIT_PWL_5; + if (td_params->config_flags & TDX_CONFIG_FLAGS_MAX_GPAW) tdx_set_mirror_root_level(kvm, 5); - } else { - kvm->arch.gfn_direct_bits = TDX_SHARED_BIT_PWL_4; + else tdx_set_mirror_root_level(kvm, 4); - } kvm_tdx->state = TD_STATE_INITIALIZED; out: -- 2.55.0.970.g62bdec98f9-goog