From nobody Sun Feb 8 18:30:13 2026 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E244633343F; Tue, 6 Jan 2026 10:25:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767695109; cv=none; b=Vyv/lqQVNnm4/6B9RQSN+wYrKDJvblcj/jqL1u8ndftOIBX+iOndHWLfxhTGPetwTUVw691/84NSe1FxZV9o1meAwuc7J6WCYPhCPyz7lAF6l7cFEGGpB7CtVGgviG1HS29cggrNBlJKrxmgZX3UtqkEMDXTk9Ph0U+jBUyznb4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767695109; c=relaxed/simple; bh=9WemXhIcKEOzBmDaVfEziMNELHtArYfBszBdtuSN710=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gbPk44nJ9fUClM/xB2yF+GD2YolzeZKUpUrNX803FwmUfDH3NHtnZL3vm/36Rhp1edYJOHReXhIvWgl5LAM5V77AauP9iU2QG541Tae6rbeJJC7hlywgn70MIGMZjcRAV7LDThZpr+sGLZUQzPa2h/WrPiI1rIHdkVF5s0oWnfg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=FcJ6LkEU; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="FcJ6LkEU" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1767695108; x=1799231108; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=9WemXhIcKEOzBmDaVfEziMNELHtArYfBszBdtuSN710=; b=FcJ6LkEU+64qGNan8oSWoakP4Tjf0xku8aZGeR09oydtf8YcOiOGR9pc ahuu+CU/BQ3N2UU4RXFBvz41VuBekSCpg9/m5kMMXocgoR390YzWFR4Y4 y2XI7sK3HIDmv/8HRMZKNocKrLXhAPP/hJOgqFDeRZAZgVR5uL9HTV29d p/y7tfLn/VkK1ZhEhWra0O3tHwBmOBd4Rf3c7xyYpbCE1LjROUQSOvRPE cKbXRb5jqvZCBCcrlSCwV7pCdqRE+/H5lh2e0Ydfbjp87p17hPs+Lk+JM ENm9u1EJu50CERYZqfRvM9OpNnWA7wt3bwog4tLGVgqGW0wvHTA1NMT2T g==; X-CSE-ConnectionGUID: Qncxhx8mRZ6r8IMKS9Qi9A== X-CSE-MsgGUID: clQP6uSmTiWTk0Sp3h6lWg== X-IronPort-AV: E=McAfee;i="6800,10657,11662"; a="86645828" X-IronPort-AV: E=Sophos;i="6.21,204,1763452800"; d="scan'208";a="86645828" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jan 2026 02:25:07 -0800 X-CSE-ConnectionGUID: 2QYusNpMSKGDujp5XjzsOQ== X-CSE-MsgGUID: Y/hOs/sZRWmRzIvJaGe/zw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,204,1763452800"; d="scan'208";a="202246964" Received: from yzhao56-desk.sh.intel.com ([10.239.47.19]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jan 2026 02:25:00 -0800 From: Yan Zhao To: pbonzini@redhat.com, seanjc@google.com Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org, rick.p.edgecombe@intel.com, dave.hansen@intel.com, kas@kernel.org, tabba@google.com, ackerleytng@google.com, michael.roth@amd.com, david@kernel.org, vannapurve@google.com, sagis@google.com, vbabka@suse.cz, thomas.lendacky@amd.com, nik.borisov@suse.com, pgonda@google.com, fan.du@intel.com, jun.miao@intel.com, francescolavra.fl@gmail.com, jgross@suse.com, ira.weiny@intel.com, isaku.yamahata@intel.com, xiaoyao.li@intel.com, kai.huang@intel.com, binbin.wu@linux.intel.com, chao.p.peng@intel.com, chao.gao@intel.com, yan.y.zhao@intel.com Subject: [PATCH v3 17/24] KVM: TDX: Get/Put DPAMT page pair only when mapping size is 4KB Date: Tue, 6 Jan 2026 18:23:04 +0800 Message-ID: <20260106102304.25211-1-yan.y.zhao@intel.com> X-Mailer: git-send-email 2.43.2 In-Reply-To: <20260106101646.24809-1-yan.y.zhao@intel.com> References: <20260106101646.24809-1-yan.y.zhao@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Kirill A. Shutemov" Invoke tdx_pamt_{get/put}() to add/remove Dynamic PAMT page pair for guest private memory only when the S-EPT mapping size is 4KB. When the mapping size is greater than 4KB, static PAMT pages are used. No need to install/uninstall extra PAMT pages dynamically. Signed-off-by: Kirill A. Shutemov [Yan: Move level checking to callers of tdx_pamt_{get/put}()] Signed-off-by: Yan Zhao --- v3: - new patch Checking for 4KB level was previously done inside tdx_pamt_{get/put}() in DPAMT v2 [1]. Move the checking to callers of tdx_pamt_{get/put}() in KVM to avoid introducing an extra "level" parameter to tdx_pamt_{get/put}(). This is also because the callers that could have level > 4KB are limited in KVM, i.e., only inside tdx_sept_{set/remove}_private_spte(). [1] https://lore.kernel.org/all/20250609191340.2051741-5-kirill.shutemov@li= nux.intel.com --- arch/x86/kvm/vmx/tdx.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 712aaa3d45b7..c1dc1aaae49d 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1722,9 +1722,11 @@ static int tdx_sept_set_private_spte(struct kvm *kvm= , gfn_t gfn, WARN_ON_ONCE(!is_shadow_present_pte(mirror_spte) || (mirror_spte & VMX_EPT_RWX_MASK) !=3D VMX_EPT_RWX_MASK); =20 - ret =3D tdx_pamt_get(page, &tdx->prealloc); - if (ret) - return ret; + if (level =3D=3D PG_LEVEL_4K) { + ret =3D tdx_pamt_get(page, &tdx->prealloc); + if (ret) + return ret; + } =20 /* * Ensure pre_fault_allowed is read by kvm_arch_vcpu_pre_fault_memory() @@ -1743,7 +1745,7 @@ static int tdx_sept_set_private_spte(struct kvm *kvm,= gfn_t gfn, else ret =3D tdx_mem_page_add(kvm, gfn, level, pfn); =20 - if (ret) + if (ret && level =3D=3D PG_LEVEL_4K) tdx_pamt_put(page); =20 return ret; @@ -1911,7 +1913,9 @@ static void tdx_sept_remove_private_spte(struct kvm *= kvm, gfn_t gfn, =20 tdx_quirk_reset_folio(folio, folio_page_idx(folio, page), KVM_PAGES_PER_HPAGE(level)); - tdx_pamt_put(page); + + if (level =3D=3D PG_LEVEL_4K) + tdx_pamt_put(page); } =20 /* --=20 2.43.2