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 379BFEB64D8 for ; Tue, 20 Jun 2023 23:34:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229805AbjFTXeV (ORCPT ); Tue, 20 Jun 2023 19:34:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33050 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229516AbjFTXeU (ORCPT ); Tue, 20 Jun 2023 19:34:20 -0400 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7DE2C170A; Tue, 20 Jun 2023 16:34:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1687304059; x=1718840059; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=4p6fgptBfYm9lNriizCwBuqL8+VvZ2ABtujsr03ZCJo=; b=fD7GQoQNEbsu3puNr7fQohOXatF+Xve7gpetXbwWYJZHcVhUvXrt2i5r vcaiVXh8AAjHDKxuLaFQVK/qBh8YiR9QHvcUzolzUv5PuubFNmhacht2B RecZ/nBFt6UlWiz6DBzJEVihaChgPy7EUqdGwl8kQiRBTEMdp7ZCsyBUD FpeqkrffPIzGYxjhl/b4v/0G8PDFHDHZUoMGv2qeqBXLJc0Cm4ztkucdo R8CYj80455B3u8yYqOGPAA1qYZnaS1+hwpjSsgV4pY5lDBFXDCxNLCs4q f6ShiDW3p57XMUgRLRyRwN13iG4bJhbHlnx/ZPHqMyTcyn7SWgzjRAC5N g==; X-IronPort-AV: E=McAfee;i="6600,9927,10747"; a="340352261" X-IronPort-AV: E=Sophos;i="6.00,258,1681196400"; d="scan'208";a="340352261" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jun 2023 16:34:13 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10747"; a="888427785" X-IronPort-AV: E=Sophos;i="6.00,258,1681196400"; d="scan'208";a="888427785" Received: from rashmigh-mobl.amr.corp.intel.com (HELO [10.255.228.28]) ([10.255.228.28]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jun 2023 16:34:08 -0700 Message-ID: <90ff7c36-9b2e-c791-dc26-3644b9ff20df@intel.com> Date: Tue, 20 Jun 2023 16:34:08 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH v8 1/2] x86/tdx: Retry TDVMCALL_MAP_GPA() when needed Content-Language: en-US To: Dexuan Cui , ak@linux.intel.com, arnd@arndb.de, bp@alien8.de, brijesh.singh@amd.com, dan.j.williams@intel.com, dave.hansen@linux.intel.com, haiyangz@microsoft.com, hpa@zytor.com, jane.chu@oracle.com, kirill.shutemov@linux.intel.com, kys@microsoft.com, linux-arch@vger.kernel.org, linux-hyperv@vger.kernel.org, luto@kernel.org, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, sathyanarayanan.kuppuswamy@linux.intel.com, seanjc@google.com, tglx@linutronix.de, tony.luck@intel.com, wei.liu@kernel.org, x86@kernel.org, mikelley@microsoft.com Cc: linux-kernel@vger.kernel.org, Tianyu.Lan@microsoft.com, rick.p.edgecombe@intel.com References: <20230620154830.25442-1-decui@microsoft.com> <20230620154830.25442-2-decui@microsoft.com> From: Dave Hansen In-Reply-To: <20230620154830.25442-2-decui@microsoft.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/20/23 08:48, Dexuan Cui wrote: > -static bool tdx_enc_status_changed(unsigned long vaddr, int numpages, bool enc) > +static bool tdx_map_gpa(phys_addr_t start, phys_addr_t end, bool enc) > { > - phys_addr_t start = __pa(vaddr); > - phys_addr_t end = __pa(vaddr + numpages * PAGE_SIZE); > + const int max_retries_per_page = 3; > + struct tdx_hypercall_args args; > + u64 map_fail_paddr, ret; > + int retry_count = 0; > > if (!enc) { > /* Set the shared (decrypted) bits: */ > @@ -718,12 +720,49 @@ static bool tdx_enc_status_changed(unsigned long vaddr, int numpages, bool enc) > end |= cc_mkdec(0); > } > > - /* > - * Notify the VMM about page mapping conversion. More info about ABI > - * can be found in TDX Guest-Host-Communication Interface (GHCI), > - * section "TDG.VP.VMCALL" > - */ > - if (_tdx_hypercall(TDVMCALL_MAP_GPA, start, end - start, 0, 0)) > + while (retry_count < max_retries_per_page) { > + memset(&args, 0, sizeof(args)); > + args.r10 = TDX_HYPERCALL_STANDARD; > + args.r11 = TDVMCALL_MAP_GPA; > + args.r12 = start; > + args.r13 = end - start; > + What's wrong with: while (retry_count < max_retries_per_page) { struct tdx_hypercall_args args = { .r10 = TDX_HYPERCALL_STANDARD, .r11 = TDVMCALL_MAP_GPA, .r12 = start, .r13 = end - start }; ? Or maybe with the brackets slightly differently arranged. Why'd you declare all the variables outside the while() loop anyway?