From nobody Fri Apr 17 03:06:32 2026 Received: from mail-dl1-f73.google.com (mail-dl1-f73.google.com [74.125.82.73]) (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 6943E3793BD for ; Mon, 23 Feb 2026 21:43:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771883031; cv=none; b=AOtAfjZYhrMUyDYi9iMsXP9aEUy/QXLKKU7rfigLQE5KYbtzRz7VP1pgIZ82XIevkeudbmfb8rgHgrLVhe3FjkoaNn2pabItafRpuwAoIaXeadTG/qPdJH/md+GJ+14VEKucXfYiCDAPLgExThkkn4sTYnMqaj84ZrXZmWiZduw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771883031; c=relaxed/simple; bh=kxeW6DG1v1HKEQ+pz2m5v66qJI6E72ZH+f+bezuzOfc=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=rFogLW+kBdm0QYkmFlHSBC3givOJkjH6HImpc0mRFeS8BQwDwwASBuncTzzdnKo3eySR3eAe30O6sljrNcZYSqnobjslF8CSnQAwhMy2C3mfqBy8rO5oWPkdmGOF5EFR0ChaybiH7iVciRm0ix+o+BqOAQjpSlllEs0bx79F100= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--changyuanl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=zRSJKHWK; arc=none smtp.client-ip=74.125.82.73 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--changyuanl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="zRSJKHWK" Received: by mail-dl1-f73.google.com with SMTP id a92af1059eb24-1270dcd11c1so6362476c88.0 for ; Mon, 23 Feb 2026 13:43:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1771883028; x=1772487828; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=pQoX++6jRv8xueXbzG+0cc+xPst310WvznBVds3LE6o=; b=zRSJKHWKUmGP+NOfKup3sQaGt2MeaawiXtvlz6i9hd+PKvXiL6DNWYN1GK8TpGSO+y Fzy/NsQqSAbEGe49eK3S8n6/AOGzWesLtVuEPIEz8mdjaxusqHBwNz+ARONB9XEANrpP wywXlkYoU2w2SzliYi9uvNTBIstPNrhomsGSp0RSgcktGVlfAMIUAUh2+ZfOihnEXYlz YYn3dbvG4jujAWrQcVtAHDacFGTxPrx8myhcJoSNoWPAyKcJBcvi85XxiYt7NjYMheB4 QEcywHOCk9b15RdUknNbkyIOXWyPMvNVj0+SfJQoxr1jDvYaY10zGqU4qDPp7ko03Q05 Yfeg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771883028; x=1772487828; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=pQoX++6jRv8xueXbzG+0cc+xPst310WvznBVds3LE6o=; b=vtKqBI0FMgSeY1UKUjUJkpvJXAVoUybdqdr0CtvQwGyRrusGNC1hh3pPCsnQJUGaNn tP59vx0WueHDI3V1vWfvrAIB3iNAjjkomf91uUg/HTprIc8urBTYOD47du/lwI87pppI ZG0ZKpYCZpSkNMLUEUS0LbNK15pRe5PMH9xWPKkMMeoZ5cvWA4Yd36+hzMALuJmF7tqe X2WS3SZBafYUBa+un07xxr31yn2C84xZFA+51Y/91k2SalQPqN5cn9/NbxA0Ls2S16a2 GmF13ol0P0Myt9f9ztwArHh2O4Do9WfGct5kuXCUHgAE3wDepSe/1Qaxwfk2YL1BVVbT A3Kg== X-Forwarded-Encrypted: i=1; AJvYcCU9gbLr7BUqNY+Ujw72oZ92FkoyBT5sTzs9QL9vik31+HFGXe0fCBoM00RCoYaAJlkzUKaYLei47Ypy2UU=@vger.kernel.org X-Gm-Message-State: AOJu0Yw0oc8DN6vcRBphMTPdLK2f8Ix2Md9JrA8TW1mpIG3iDuGyE7GV qRMhOE3sbTCjB5PVsimCgkclPKHGbMLdO3VYPOsmOiQc65x2bQS6hwC8WIauhw+O8An7NAWB0uX 6kBbRXUZut3F+z8RsZ7+Ozw== X-Received: from dlbur22-n1.prod.google.com ([2002:a05:7022:ea56:10b0:121:7afb:490]) (user=changyuanl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:4593:b0:11d:c22e:a131 with SMTP id a92af1059eb24-1276acda401mr4301273c88.3.1771883028380; Mon, 23 Feb 2026 13:43:48 -0800 (PST) Date: Mon, 23 Feb 2026 13:43:36 -0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.53.0.371.g1d285c8824-goog Message-ID: <20260223214336.722463-1-changyuanl@google.com> Subject: [PATCH] KVM: TDX: Set SIGNIFCANT_INDEX flag for supported CPUIDs From: Changyuan Lyu To: Sean Christopherson , Paolo Bonzini , Isaku Yamahata , Xiaoyao Li Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Kiryl Shutsemau , Rick Edgecombe , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, Changyuan Lyu Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Set the KVM_CPUID_FLAG_SIGNIFCANT_INDEX flag in the kvm_cpuid_entry2 structures returned by KVM_TDX_CAPABILITIES if the CPUID is indexed. This ensures consistency with the CPUID entries returned by KVM_GET_SUPPORTED_CPUID. Additionally, add a WARN_ON_ONCE() to verify that the TDX module's reported entries align with KVM's expectations regarding indexed CPUID functions. Suggested-by: Sean Christopherson Signed-off-by: Changyuan Lyu --- arch/x86/kvm/vmx/tdx.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 2d7a4d52ccfb4..0c524f9a94a6c 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -172,9 +172,15 @@ static void td_init_cpuid_entry2(struct kvm_cpuid_entr= y2 *entry, unsigned char i entry->ecx =3D (u32)td_conf->cpuid_config_values[idx][1]; entry->edx =3D td_conf->cpuid_config_values[idx][1] >> 32; =20 - if (entry->index =3D=3D KVM_TDX_CPUID_NO_SUBLEAF) + if (entry->index =3D=3D KVM_TDX_CPUID_NO_SUBLEAF) { entry->index =3D 0; + entry->flags &=3D ~KVM_CPUID_FLAG_SIGNIFCANT_INDEX; + } else { + entry->flags |=3D KVM_CPUID_FLAG_SIGNIFCANT_INDEX; + } =20 + WARN_ON_ONCE(cpuid_function_is_indexed(entry->function) !=3D + !!(entry->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX)); /* * The TDX module doesn't allow configuring the guest phys addr bits * (EAX[23:16]). However, KVM uses it as an interface to the userspace --=20 2.53.0.371.g1d285c8824-goog