From nobody Mon Jun 8 06:38:17 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 6D459466B6A; Fri, 5 Jun 2026 21:25:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780694733; cv=none; b=ha9Xk3VIdvLY9ztAlBkcglAERwm5OSFkWdzZai4VlabQqVu0GPYdt+Tw12eYa8cVvp9Ai8D39yakdYuLgG2APFlF0h81MKZ57jmXZ/JIySULenEGHAVTXQlmHt//xIM3TyJx6iNHFnjVZaCMDzncfvPZf04T5b1ktiEPpAUeE+A= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780694733; c=relaxed/simple; bh=M5XNis3jfmFWeAznJNZ8yn0Ht+565xPlVz+E1XiYWV0=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=Vnwk5A/YTFX1GNIBpyERroNOKoj5w7nMfcavVgIDYll7LJ0Us0Tc2RHlIt0nVcWdQZaNwP0RSL3qibhiyrEebocZ0HKEUEOUmzCyVG2Khh55eVoZ8cYqfLviU8Larv+D/6wzHJdnm3mhMIS75uurheVOC2w698og++6ftmmrNSs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Bar5qole; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=P24WzIpI; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Bar5qole"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="P24WzIpI" Date: Fri, 05 Jun 2026 21:25:29 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1780694731; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xJZUpukOHXpMi8Qjg7X4WpbxiDsHc4qZ3Z2TDWdU5+4=; b=Bar5qoleJGI7jYxssrzV2yNtDAdr5V+8CK+JM27N3Zw4dWYDhYx72BjYH3qXiQtWfmdcWi 0rq35wFZvgJk3PrQw0WY+DLm9TVQtxBnSLDu3IfgFsSy241x6PPxdidS7N1m/cUhGMXJSI 4X0gxa289ZibEGGhB282GPELL5mMoiw3burLpnLKgriOv0xkNldRJ7x9gNKE6gsQqrd4ID kq5ohnlmE5GrLoQc/1jhIEj/VsJsTAXl6Qi2b7JaMP5QiZOnFKPj6zyn2y9vJ3PhuKr54L qzuFDACG2OfuDuJxDBOAxXWTl1OzrHtS3JXOJVscRLFbmc6KklZ6gSqTOU4/9g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1780694731; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xJZUpukOHXpMi8Qjg7X4WpbxiDsHc4qZ3Z2TDWdU5+4=; b=P24WzIpIbaq16pfjYMsHdd5aEVh7R4KQP+71c2R5Ijbzh384Y4+Z2WnjnMTO0+a6xPH+/L 6o3VPPV+U04yaNCQ== From: "tip-bot2 for Chao Gao" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/tdx] coco/tdx-host: Introduce a "tdx_host" device Cc: Chao Gao , Dave Hansen , Jonathan Cameron , Tony Lindgren , Xu Yilun , Kai Huang , "Kiryl Shutsemau (Meta)" , Xiaoyao Li , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20260520133909.409394-7-chao.gao@intel.com> References: <20260520133909.409394-7-chao.gao@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <178069472981.710.16267927939954097112.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the x86/tdx branch of tip: Commit-ID: 59783353467958517a3e511394d7ab3aed03bc6a Gitweb: https://git.kernel.org/tip/59783353467958517a3e511394d7ab3ae= d03bc6a Author: Chao Gao AuthorDate: Wed, 20 May 2026 15:28:52 -07:00 Committer: Dave Hansen CommitterDate: Wed, 03 Jun 2026 08:14:51 -07:00 coco/tdx-host: Introduce a "tdx_host" device TDX depends on a platform firmware module that runs on the CPU. Unlike other CoCo architectures, TDX has no hardware "device" running the show, just a blob on the CPU. Create a virtual device to anchor interactions with this platform firmware. This lets later code: - expose metadata: TDX module version, seamldr version, to userspace as device attributes - implement firmware uploader APIs (which are tied to a device) to support TDX module runtime updates Use a faux device because the TDX module is singular within the system and has no platform resources. Using a faux device eliminates the need to create a stub bus. The call to tdx_get_sysinfo() ensures that the TDX module is ready to provide services. Note that AMD has a PCI device for the PSP for SEV and ARM CCA will likely have a faux device [1]. Thanks to Dan and Yilun for all the help on this one. [ dhansen: trim changelog ] Signed-off-by: Chao Gao Signed-off-by: Dave Hansen Reviewed-by: Jonathan Cameron Reviewed-by: Tony Lindgren Reviewed-by: Xu Yilun Reviewed-by: Kai Huang Reviewed-by: Kiryl Shutsemau (Meta) Reviewed-by: Xiaoyao Li Link: https://lore.kernel.org/all/2025073035-bulginess-rematch-b92e@gregkh/= # [1] Link: https://patch.msgid.link/20260520133909.409394-7-chao.gao@intel.com --- arch/x86/virt/vmx/tdx/tdx.c | 2 +- drivers/virt/coco/Kconfig | 2 +- drivers/virt/coco/Makefile | 1 +- drivers/virt/coco/tdx-host/Kconfig | 4 ++- drivers/virt/coco/tdx-host/Makefile | 1 +- drivers/virt/coco/tdx-host/tdx-host.c | 43 ++++++++++++++++++++++++++- 6 files changed, 52 insertions(+), 1 deletion(-) create mode 100644 drivers/virt/coco/tdx-host/Kconfig create mode 100644 drivers/virt/coco/tdx-host/Makefile create mode 100644 drivers/virt/coco/tdx-host/tdx-host.c diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c index b329791..5fb0441 100644 --- a/arch/x86/virt/vmx/tdx/tdx.c +++ b/arch/x86/virt/vmx/tdx/tdx.c @@ -1527,7 +1527,7 @@ const struct tdx_sys_info *tdx_get_sysinfo(void) =20 return (const struct tdx_sys_info *)&tdx_sysinfo; } -EXPORT_SYMBOL_FOR_KVM(tdx_get_sysinfo); +EXPORT_SYMBOL_FOR_MODULES(tdx_get_sysinfo, "kvm-intel,tdx-host"); =20 u32 tdx_get_nr_guest_keyids(void) { diff --git a/drivers/virt/coco/Kconfig b/drivers/virt/coco/Kconfig index df1cfaf..f7691f6 100644 --- a/drivers/virt/coco/Kconfig +++ b/drivers/virt/coco/Kconfig @@ -17,5 +17,7 @@ source "drivers/virt/coco/arm-cca-guest/Kconfig" source "drivers/virt/coco/guest/Kconfig" endif =20 +source "drivers/virt/coco/tdx-host/Kconfig" + config TSM bool diff --git a/drivers/virt/coco/Makefile b/drivers/virt/coco/Makefile index cb52021..b323b0a 100644 --- a/drivers/virt/coco/Makefile +++ b/drivers/virt/coco/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_EFI_SECRET) +=3D efi_secret/ obj-$(CONFIG_ARM_PKVM_GUEST) +=3D pkvm-guest/ obj-$(CONFIG_SEV_GUEST) +=3D sev-guest/ obj-$(CONFIG_INTEL_TDX_GUEST) +=3D tdx-guest/ +obj-$(CONFIG_INTEL_TDX_HOST) +=3D tdx-host/ obj-$(CONFIG_ARM_CCA_GUEST) +=3D arm-cca-guest/ obj-$(CONFIG_TSM) +=3D tsm-core.o obj-$(CONFIG_TSM_GUEST) +=3D guest/ diff --git a/drivers/virt/coco/tdx-host/Kconfig b/drivers/virt/coco/tdx-hos= t/Kconfig new file mode 100644 index 0000000..cfe81b9 --- /dev/null +++ b/drivers/virt/coco/tdx-host/Kconfig @@ -0,0 +1,4 @@ +config TDX_HOST_SERVICES + tristate + depends on INTEL_TDX_HOST + default m diff --git a/drivers/virt/coco/tdx-host/Makefile b/drivers/virt/coco/tdx-ho= st/Makefile new file mode 100644 index 0000000..e61e749 --- /dev/null +++ b/drivers/virt/coco/tdx-host/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_TDX_HOST_SERVICES) +=3D tdx-host.o diff --git a/drivers/virt/coco/tdx-host/tdx-host.c b/drivers/virt/coco/tdx-= host/tdx-host.c new file mode 100644 index 0000000..c778853 --- /dev/null +++ b/drivers/virt/coco/tdx-host/tdx-host.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * TDX host user interface driver + * + * Copyright (C) 2025 Intel Corporation + */ + +#include +#include +#include + +#include +#include + +static const struct x86_cpu_id tdx_host_ids[] =3D { + X86_MATCH_FEATURE(X86_FEATURE_TDX_HOST_PLATFORM, NULL), + {} +}; +MODULE_DEVICE_TABLE(x86cpu, tdx_host_ids); + +static struct faux_device *fdev; + +static int __init tdx_host_init(void) +{ + if (!x86_match_cpu(tdx_host_ids) || !tdx_get_sysinfo()) + return -ENODEV; + + fdev =3D faux_device_create(KBUILD_MODNAME, NULL, NULL); + if (!fdev) + return -ENODEV; + + return 0; +} +module_init(tdx_host_init); + +static void __exit tdx_host_exit(void) +{ + faux_device_destroy(fdev); +} +module_exit(tdx_host_exit); + +MODULE_DESCRIPTION("TDX Host Services"); +MODULE_LICENSE("GPL");