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 9A9B9C001DF for ; Sun, 22 Oct 2023 16:51:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232114AbjJVQvr (ORCPT ); Sun, 22 Oct 2023 12:51:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229500AbjJVQvp (ORCPT ); Sun, 22 Oct 2023 12:51:45 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2155CFB for ; Sun, 22 Oct 2023 09:51:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697993503; x=1729529503; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=2h1MLsEUAKWtQrKuqZMPzdZyua2XzLtNlrV8BMgQOg4=; b=BlCXXu4uxFhn/1jmAnyliXqLI0Y3BJRfzaeQ4ZzEbdPZlu791Y9SHiX2 SrKoHEYOch2LGMxw0GwOeDYeCrQkh0kIDbO59Yhif3Ng9wHXQWnnT7kT3 y238I9UaTIovuNkUu1oB/nGL/MgnUnuUAvgC1cHDLBTtPpOGeiiZDVKyt lHZF33PESUQSbrscZC6pyW04S1XeuxRD+UiTDtaTOSIL+X2KmOoNMzs/b SCDq9k0mzogbYRPTSvuMkA3n3ER7EGVqHKxBxi2Nfx6eimzzHaKZfQnTK U/T+hMo1Pd5QyPY8qyK1malcKDuL8e4c64JYLIDJe/7AD1sRfVtEx7+Y0 g==; X-IronPort-AV: E=McAfee;i="6600,9927,10871"; a="371786930" X-IronPort-AV: E=Sophos;i="6.03,243,1694761200"; d="scan'208";a="371786930" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Oct 2023 09:51:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10871"; a="823750225" X-IronPort-AV: E=Sophos;i="6.03,243,1694761200"; d="scan'208";a="823750225" Received: from mozdogan-mobl1.amr.corp.intel.com (HELO [10.209.73.165]) ([10.209.73.165]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Oct 2023 09:51:41 -0700 Message-ID: Date: Sun, 22 Oct 2023 09:51:42 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6] x86/tdx: Dump TDX Version During TD Bootup To: Yi Sun , tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, peterz@infradead.org, x86@kernel.org Cc: kirill.shutemov@linux.intel.com, kai.huang@intel.com, nik.borisov@suse.com, linux-kernel@vger.kernel.org, heng.su@intel.com, yi.sun@linux.intel.com, Dongcheng Yan References: <20231022063122.2812190-1-yi.sun@intel.com> Content-Language: en-US From: Kuppuswamy Sathyanarayanan In-Reply-To: <20231022063122.2812190-1-yi.sun@intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/21/2023 11:31 PM, Yi Sun wrote: > Different versions of TDX have significant differences, as stated in the > "Intel® TDX Module Incompatibilities between v1.0 and v1.5" reference. > > It would be useful for TD users to be aware of the vendor and version of > the current TDX in use. Users could expect different results when checking > CPIUD or reading MSR in the user space, depending on the TDX version. > Additionally, refer to the TDX version when reporting issues. > > Reviewed-by: Kirill A. Shutemov > Reviewed-by: Nikolay Borisov > Co-developed-by: Dongcheng Yan > Signed-off-by: Dongcheng Yan > Signed-off-by: Yi Sun > > --- > V5 -> V6: > - Remove random warnings at each step. Print the error details and > presumed TDX version in common code. (Dave Hansen) > > - Remove useless assignment and cast. Re-zeroed the input args > between tdcalls. Refine the comments. (Dave Hansen) > > V4 -> V5: > - Print the version info inside the function detect_tdx_version, but > not tdx_early_init(). Remove the structure tdg_sys_info, but have 3 > local variables instead. (Huang, Kai) > > V3 -> V4: > - Rebase the patch on top of the latest tip tree. (Huang, Kai) > - Change the return value of function tdg_get_sysinfo as void, and > zero out tdg_sys_info when error occurs. (Kuppuswamy Sathyanarayanan) > > V2 -> V3: > - Move the allocation of struct tdg_sys_info on stack inside > tdx_early_init() and pass down to tdg_get_sysinfo() to fill. > (Kirill Shutemov) > > V1 -> V2: > - Move the defination of field IDs and the struct tdg_sys_info to tdx.c. > (Kuppuswamy Sathyanarayanan) > > diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c > index 3e6dbd2199cf..20e911241e56 100644 > --- a/arch/x86/coco/tdx/tdx.c > +++ b/arch/x86/coco/tdx/tdx.c > @@ -37,6 +37,15 @@ > > #define TDREPORT_SUBTYPE_0 0 > > +/* > + * TDX metadata base field id, used by TDCALL TDG.SYS.RD > + * See TDX ABI Spec Global Metadata Fields > + */ > +#define TDX_SYS_VENDOR_ID_FID 0x0800000200000000ULL > +#define TDX_SYS_MINOR_FID 0x0800000100000003ULL > +#define TDX_SYS_MAJOR_FID 0x0800000100000004ULL > +#define TDX_VENDOR_INTEL 0x8086 > + > /* Called from __tdx_hypercall() for unrecoverable failure */ > noinstr void __noreturn __tdx_hypercall_failed(void) > { > @@ -800,6 +809,56 @@ static bool tdx_enc_status_change_finish(unsigned long vaddr, int numpages, > return true; > } > > +/* > + * Detect TDX Module version info from TDG.SYS.RD TDCALL > + */ > +static void detect_tdx_version(void) > +{ > + struct tdx_module_args args = {}; > + u16 major_version = 0; > + u16 minor_version = 0; > + u32 vendor_id = 0; > + u64 ret = 0; Since you overwrite all above values, I think you can skip initialization. > + > + args.rdx = TDX_SYS_VENDOR_ID_FID; > + ret = __tdcall_ret(TDG_SYS_RD, &args); > + if (ret) > + goto err_out; > + > + vendor_id = args.r8; > + > + memset(&args, 0, sizeof(args)); > + args.rdx = TDX_SYS_MAJOR_FID; > + ret = __tdcall_ret(TDG_SYS_RD, &args); > + if (ret) > + goto err_out; > + > + major_version = args.r8; > + > + memset(&args, 0, sizeof(args)); > + args.rdx = TDX_SYS_MINOR_FID; > + ret = __tdcall_ret(TDG_SYS_RD, &args); > + if (ret) > + goto err_out; > + > + minor_version = args.r8; > + > + pr_info("TDX detected. TDX version:%u.%u VendorID:%x\n", > + major_version, minor_version, vendor_id); Since TDX prefix is part of pr_info, you can just use "Guest detected. version:..." > + > + return; > + > +err_out: > + if (TDCALL_RETURN_CODE(ret) == TDCALL_INVALID_OPERAND) > + pr_info("TDG.SYS.RD not available\n"); > + else > + pr_info("TDG.SYS.RD unknown error (%llu), reading field %llu\n", > + ret, args.rdx); > + > + pr_info("Assuming TDX version:1.x (x<5) VendorID:%x\n", > + TDX_VENDOR_INTEL); > +} > + > void __init tdx_early_init(void) > { > struct tdx_module_args args = { > @@ -867,5 +926,5 @@ void __init tdx_early_init(void) > */ > x86_cpuinit.parallel_bringup = false; > > - pr_info("Guest detected\n"); > + detect_tdx_version(); > } > diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h > index f74695dea217..10b6c61e835e 100644 > --- a/arch/x86/include/asm/shared/tdx.h > +++ b/arch/x86/include/asm/shared/tdx.h > @@ -17,6 +17,8 @@ > #define TDG_MR_REPORT 4 > #define TDG_MEM_PAGE_ACCEPT 6 > #define TDG_VM_WR 8 > +/* The TDCALL TDG.SYS.RD originates from TDX version 1.5 */ > +#define TDG_SYS_RD 11 > > /* TDCS fields. To be used by TDG.VM.WR and TDG.VM.RD module calls */ > #define TDCS_NOTIFY_ENABLES 0x9100000000000010 -- Sathyanarayanan Kuppuswamy Linux Kernel Developer