From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0CE03C433F5 for ; Mon, 7 Mar 2022 22:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238513AbiCGW2n (ORCPT ); Mon, 7 Mar 2022 17:28:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241174AbiCGW2k (ORCPT ); Mon, 7 Mar 2022 17:28:40 -0500 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 011FD2715A for ; Mon, 7 Mar 2022 14:27:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1646692064; x=1678228064; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0MdClp/QeOgyvufdvQeF8M9rZ7ABzB7YXW6LninCo+E=; b=SYlL85AJrdtm5slalt4db/wR+BzvYpRmCyV78JNut3OSrItv5xOVBM6i DS6cBqCXUvIY0Z3DhZNZ2PQNHVdZvZ5TZoNBLGm1BuGBO5c601UdvLsde xDgcbR49DzQtKgvjweCM7bL8j6KxmNksO6jJF56l4SCpaTNJ2OqtyvZET i0A+wzBmSu/ryQsnI62T2wuNjLInkNb05sMAzaW8FbDVjQA5UMgFhwGbs sochFZTcfQqJVLDH9L3yRqQz8wX+/F3ZPADaXdgq9TuGM1yw2uqQ2uVae XiS5/1+bmAu/ko9N0/xhqRfkNmNZrt/pX56cuzMXphPl5+fvDdWzWUDa9 A==; X-IronPort-AV: E=McAfee;i="6200,9189,10279"; a="317754877" X-IronPort-AV: E=Sophos;i="5.90,163,1643702400"; d="scan'208";a="317754877" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Mar 2022 14:27:44 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,163,1643702400"; d="scan'208";a="641504713" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga002.fm.intel.com with ESMTP; 07 Mar 2022 14:27:37 -0800 Received: by black.fi.intel.com (Postfix, from userid 1000) id C627B1D6; Tue, 8 Mar 2022 00:27:55 +0200 (EET) From: "Kirill A. Shutemov" To: kirill.shutemov@linux.intel.com Cc: aarcange@redhat.com, ak@linux.intel.com, bp@alien8.de, brijesh.singh@amd.com, dan.j.williams@intel.com, dave.hansen@intel.com, dave.hansen@linux.intel.com, david@redhat.com, hpa@zytor.com, jgross@suse.com, jmattson@google.com, joro@8bytes.org, jpoimboe@redhat.com, knsathya@kernel.org, linux-kernel@vger.kernel.org, luto@kernel.org, mingo@redhat.com, pbonzini@redhat.com, peterz@infradead.org, sathyanarayanan.kuppuswamy@linux.intel.com, sdeep@vmware.com, seanjc@google.com, tglx@linutronix.de, thomas.lendacky@amd.com, tony.luck@intel.com, vkuznets@redhat.com, wanpengli@tencent.com, x86@kernel.org Subject: [PATCHv5.1 12/30] x86/tdx: Detect TDX at early kernel decompression time Date: Tue, 8 Mar 2022 01:27:48 +0300 Message-Id: <20220307222748.2318-1-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220302142806.51844-13-kirill.shutemov@linux.intel.com> References: <20220302142806.51844-13-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kuppuswamy Sathyanarayanan The early decompression code does port I/O for its console output. But, handling the decompression-time port I/O demands a different approach from normal runtime because the IDT required to support #VE based port I/O emulation is not yet set up. Paravirtualizing I/O calls during the decompression step is acceptable because the decompression code doesn't have a lot of call sites to IO instruction. To support port I/O in decompression code, TDX must be detected before the decompression code might do port I/O. Detect whether the kernel runs in a TDX guest. Add an early_is_tdx_guest() interface to query the cached TDX guest status in the decompression code. TDX is detected with CPUID. Make cpuid_count() accessible outside boot/cpuflags.c. TDX detection in the main kernel is very similar. Move common bits into . The actual port I/O paravirtualization will come later in the series. Reviewed-by: Tony Luck Signed-off-by: Kuppuswamy Sathyanarayanan Signed-off-by: Kirill A. Shutemov Acked-by: Dave Hansen --- v5.1: - Drop BUILD_BUG_ON() --- arch/x86/boot/compressed/Makefile | 1 + arch/x86/boot/compressed/misc.c | 8 ++++++++ arch/x86/boot/compressed/misc.h | 2 ++ arch/x86/boot/compressed/tdx.c | 26 ++++++++++++++++++++++++++ arch/x86/boot/compressed/tdx.h | 15 +++++++++++++++ arch/x86/boot/cpuflags.c | 3 +-- arch/x86/boot/cpuflags.h | 1 + arch/x86/include/asm/shared/tdx.h | 8 ++++++++ arch/x86/include/asm/tdx.h | 4 +--- 9 files changed, 63 insertions(+), 5 deletions(-) create mode 100644 arch/x86/boot/compressed/tdx.c create mode 100644 arch/x86/boot/compressed/tdx.h create mode 100644 arch/x86/include/asm/shared/tdx.h diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 6115274fe10f..732f6b21ecbd 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -101,6 +101,7 @@ ifdef CONFIG_X86_64 endif vmlinux-objs-$(CONFIG_ACPI) += $(obj)/acpi.o +vmlinux-objs-$(CONFIG_INTEL_TDX_GUEST) += $(obj)/tdx.o vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o efi-obj-$(CONFIG_EFI_STUB) = $(objtree)/drivers/firmware/efi/libstub/lib.a diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index a4339cb2d247..2b1169869b96 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -370,6 +370,14 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, lines = boot_params->screen_info.orig_video_lines; cols = boot_params->screen_info.orig_video_cols; + /* + * Detect TDX guest environment. + * + * It has to be done before console_init() in order to use + * paravirtualized port I/O operations if needed. + */ + early_tdx_detect(); + console_init(); /* diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 16ed360b6692..0d8e275a9d96 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -28,6 +28,8 @@ #include #include +#include "tdx.h" + #define BOOT_CTYPE_H #include diff --git a/arch/x86/boot/compressed/tdx.c b/arch/x86/boot/compressed/tdx.c new file mode 100644 index 000000000000..d4f195e9d1ef --- /dev/null +++ b/arch/x86/boot/compressed/tdx.c @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include "../cpuflags.h" +#include "../string.h" + +#include + +static bool tdx_guest_detected; + +bool early_is_tdx_guest(void) +{ + return tdx_guest_detected; +} + +void early_tdx_detect(void) +{ + u32 eax, sig[3]; + + cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, &sig[0], &sig[2], &sig[1]); + + if (memcmp(TDX_IDENT, sig, sizeof(sig))) + return; + + /* Cache TDX guest feature status */ + tdx_guest_detected = true; +} diff --git a/arch/x86/boot/compressed/tdx.h b/arch/x86/boot/compressed/tdx.h new file mode 100644 index 000000000000..a7bff6ae002e --- /dev/null +++ b/arch/x86/boot/compressed/tdx.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef BOOT_COMPRESSED_TDX_H +#define BOOT_COMPRESSED_TDX_H + +#include + +#ifdef CONFIG_INTEL_TDX_GUEST +void early_tdx_detect(void); +bool early_is_tdx_guest(void); +#else +static inline void early_tdx_detect(void) { }; +static inline bool early_is_tdx_guest(void) { return false; } +#endif + +#endif /* BOOT_COMPRESSED_TDX_H */ diff --git a/arch/x86/boot/cpuflags.c b/arch/x86/boot/cpuflags.c index a0b75f73dc63..a83d67ec627d 100644 --- a/arch/x86/boot/cpuflags.c +++ b/arch/x86/boot/cpuflags.c @@ -71,8 +71,7 @@ int has_eflag(unsigned long mask) # define EBX_REG "=b" #endif -static inline void cpuid_count(u32 id, u32 count, - u32 *a, u32 *b, u32 *c, u32 *d) +void cpuid_count(u32 id, u32 count, u32 *a, u32 *b, u32 *c, u32 *d) { asm volatile(".ifnc %%ebx,%3 ; movl %%ebx,%3 ; .endif \n\t" "cpuid \n\t" diff --git a/arch/x86/boot/cpuflags.h b/arch/x86/boot/cpuflags.h index 2e20814d3ce3..475b8fde90f7 100644 --- a/arch/x86/boot/cpuflags.h +++ b/arch/x86/boot/cpuflags.h @@ -17,5 +17,6 @@ extern u32 cpu_vendor[3]; int has_eflag(unsigned long mask); void get_cpuflags(void); +void cpuid_count(u32 id, u32 count, u32 *a, u32 *b, u32 *c, u32 *d); #endif diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h new file mode 100644 index 000000000000..8209ba9ffe1a --- /dev/null +++ b/arch/x86/include/asm/shared/tdx.h @@ -0,0 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_SHARED_TDX_H +#define _ASM_X86_SHARED_TDX_H + +#define TDX_CPUID_LEAF_ID 0x21 +#define TDX_IDENT "IntelTDX " + +#endif /* _ASM_X86_SHARED_TDX_H */ diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h index 1f150e7a2f8f..76cffbda0e79 100644 --- a/arch/x86/include/asm/tdx.h +++ b/arch/x86/include/asm/tdx.h @@ -6,9 +6,7 @@ #include #include #include - -#define TDX_CPUID_LEAF_ID 0x21 -#define TDX_IDENT "IntelTDX " +#include #define TDX_HYPERCALL_STANDARD 0 -- 2.34.1