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 CD72DC4167B for ; Wed, 6 Dec 2023 05:33:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376708AbjLFFcz (ORCPT ); Wed, 6 Dec 2023 00:32:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230412AbjLFFcx (ORCPT ); Wed, 6 Dec 2023 00:32:53 -0500 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED07A1A2; Tue, 5 Dec 2023 21:32:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1701840776; x=1733376776; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=L8FXHbQY2NjwwufwQG+OS1NuMlxKowjr553YIDVdUiI=; b=ALNK88VjO29zmz1PNvOk9hqh65pb/Puua3XgMbnPMsoO3ips5Xai4txw U77OEomq3tBs5Y3TCcyhY8Wgca2VFA4lZTv8DGFKviDcoHQ4i1hBXotrk UMCaIh0LfXx+WNGfgKZb0JTudx7riwiTUMrjuO7DXSao/nnOyAWedFl06 3G9RauCsWhGReMHzWLpGZ3pxdUHvj9QxevKKcDZXK/TqxQRIsilndCA/x G8t4jlfh+sO/xNxnBb2M6IV3iTOv/7ov5tE+wYBgDQvedaYQvuip44kv3 UCRLx4zuhUJliO9yZHZtVqmReO9PU40uKDVNFoNNNLri0o1ABH8bcINB9 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10915"; a="374191824" X-IronPort-AV: E=Sophos;i="6.04,254,1695711600"; d="scan'208";a="374191824" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2023 21:32:56 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10915"; a="837203391" X-IronPort-AV: E=Sophos;i="6.04,254,1695711600"; d="scan'208";a="837203391" Received: from binbinwu-mobl.ccr.corp.intel.com (HELO [10.238.10.126]) ([10.238.10.126]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2023 21:32:53 -0800 Message-ID: Date: Wed, 6 Dec 2023 13:32:50 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v17 012/116] KVM: TDX: Retry SEAMCALL on the lack of entropy error To: isaku.yamahata@intel.com Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar , David Matlack , Kai Huang , Zhi Wang , chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com References: From: Binbin Wu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/7/2023 10:55 PM, isaku.yamahata@intel.com wrote: > From: Isaku Yamahata > > Some SEAMCALL may return TDX_RND_NO_ENTROPY error when the entropy is > lacking. Retry SEAMCALL on the error following rdrand_long() to retry > RDRAND_RETRY_LOOPS times. > > Signed-off-by: Isaku Yamahata > --- > arch/x86/kvm/vmx/tdx_errno.h | 1 + > arch/x86/kvm/vmx/tdx_ops.h | 40 +++++++++++++++++++++--------------- > 2 files changed, 24 insertions(+), 17 deletions(-) > > diff --git a/arch/x86/kvm/vmx/tdx_errno.h b/arch/x86/kvm/vmx/tdx_errno.h > index 7f96696b8e7c..bb093e292fef 100644 > --- a/arch/x86/kvm/vmx/tdx_errno.h > +++ b/arch/x86/kvm/vmx/tdx_errno.h > @@ -14,6 +14,7 @@ > #define TDX_OPERAND_INVALID 0xC000010000000000ULL > #define TDX_OPERAND_BUSY 0x8000020000000000ULL > #define TDX_PREVIOUS_TLB_EPOCH_BUSY 0x8000020100000000ULL > +#define TDX_RND_NO_ENTROPY 0x8000020300000000ULL > #define TDX_VCPU_NOT_ASSOCIATED 0x8000070200000000ULL > #define TDX_KEY_GENERATION_FAILED 0x8000080000000000ULL > #define TDX_KEY_STATE_INCORRECT 0xC000081100000000ULL > diff --git a/arch/x86/kvm/vmx/tdx_ops.h b/arch/x86/kvm/vmx/tdx_ops.h > index 12fd6b8d49e0..a55977626ae3 100644 > --- a/arch/x86/kvm/vmx/tdx_ops.h > +++ b/arch/x86/kvm/vmx/tdx_ops.h > @@ -6,6 +6,7 @@ > > #include > > +#include > #include > #include > #include > @@ -17,25 +18,30 @@ > static inline u64 tdx_seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9, > struct tdx_module_args *out) > { > + int retry; > u64 ret; > > - if (out) { > - *out = (struct tdx_module_args) { > - .rcx = rcx, > - .rdx = rdx, > - .r8 = r8, > - .r9 = r9, > - }; > - ret = __seamcall_ret(op, out); > - } else { > - struct tdx_module_args args = { > - .rcx = rcx, > - .rdx = rdx, > - .r8 = r8, > - .r9 = r9, > - }; > - ret = __seamcall(op, &args); > - } > + /* Mimic the existing rdrand_long() to retry RDRAND_RETRY_LOOPS times. */ > + retry = RDRAND_RETRY_LOOPS; Nit: The value can be assigned when define. Reviewed-by: Binbin Wu > + do { > + if (out) { > + *out = (struct tdx_module_args) { > + .rcx = rcx, > + .rdx = rdx, > + .r8 = r8, > + .r9 = r9, > + }; > + ret = __seamcall_ret(op, out); > + } else { > + struct tdx_module_args args = { > + .rcx = rcx, > + .rdx = rdx, > + .r8 = r8, > + .r9 = r9, > + }; > + ret = __seamcall(op, &args); > + } > + } while (unlikely(ret == TDX_RND_NO_ENTROPY) && --retry); > if (unlikely(ret == TDX_SEAMCALL_UD)) { > /* > * SEAMCALLs fail with TDX_SEAMCALL_UD returned when VMX is off.