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 62988C433F5 for ; Tue, 8 Mar 2022 01:19:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344230AbiCHBUO (ORCPT ); Mon, 7 Mar 2022 20:20:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238576AbiCHBUM (ORCPT ); Mon, 7 Mar 2022 20:20:12 -0500 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 918D837009 for ; Mon, 7 Mar 2022 17:19:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1646702356; x=1678238356; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=9VShFtUnHahYjXoEmhuEaaKsxAaqPctuFnTiXKgAwlg=; b=D+ngteafjReZWyptzAB8yL1mNX8G/YdEODs8JzftLZDi6dn0awwK/Hpd B4GolPcx6jIKZ5vAXAF53QDxbC41nd4lz1qH7sob9q72v8wxTdwDT6eKy BK7TnmJo469HxcZRiOzXjVg8s0qryoyvxCZK+sh2z+wCLtzEwh3xSZOr1 kO/bldyF5GfFeeYvBfR71l4MYVdjz61EGeaKHmOCBMS7pmIJmnUiRcHzO 2hF/FWzC8nQ9YjyUwoFNiksCmOQlYCoCt/TWhnyBC0TgNqGqqsw4VGnh6 2skx6XwQMyhMNiSBBly8vzUacEO1w3/e+khJYy+ewHdudibksIGdjlhRQ w==; X-IronPort-AV: E=McAfee;i="6200,9189,10279"; a="340987297" X-IronPort-AV: E=Sophos;i="5.90,163,1643702400"; d="scan'208";a="340987297" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Mar 2022 17:19:16 -0800 X-IronPort-AV: E=Sophos;i="5.90,163,1643702400"; d="scan'208";a="537357528" Received: from xiaoyaol-hp-g830.ccr.corp.intel.com (HELO [10.255.31.213]) ([10.255.31.213]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Mar 2022 17:19:08 -0800 Message-ID: <4a4a672f-a21e-f50d-9289-27456923f6df@intel.com> Date: Tue, 8 Mar 2022 09:19:06 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.6.1 Subject: Re: [PATCHv5 23/30] x86/boot: Avoid #VE during boot for TDX platforms Content-Language: en-US To: "Kirill A. Shutemov" Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@intel.com, luto@kernel.org, peterz@infradead.org, sathyanarayanan.kuppuswamy@linux.intel.com, aarcange@redhat.com, ak@linux.intel.com, dan.j.williams@intel.com, david@redhat.com, hpa@zytor.com, jgross@suse.com, jmattson@google.com, joro@8bytes.org, jpoimboe@redhat.com, knsathya@kernel.org, pbonzini@redhat.com, sdeep@vmware.com, seanjc@google.com, tony.luck@intel.com, vkuznets@redhat.com, wanpengli@tencent.com, thomas.lendacky@amd.com, brijesh.singh@amd.com, x86@kernel.org, linux-kernel@vger.kernel.org References: <20220302142806.51844-1-kirill.shutemov@linux.intel.com> <20220302142806.51844-24-kirill.shutemov@linux.intel.com> <20220307223353.f7cqzqispfeltvb2@black.fi.intel.com> From: Xiaoyao Li In-Reply-To: <20220307223353.f7cqzqispfeltvb2@black.fi.intel.com> 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 3/8/2022 6:33 AM, Kirill A. Shutemov wrote: > On Mon, Mar 07, 2022 at 05:29:27PM +0800, Xiaoyao Li wrote: ... >> Even though CPUID reports MCE is supported, all the access to MCE related >> MSRs causes #VE. If they are accessed via mce_rdmsrl(), the #VE will be >> fixed up and goes to ex_handler_msr_mce(). Finally lead to panic(). > > It is not panic, but warning. Like this: > > unchecked MSR access error: RDMSR from 0x179 at rIP: 0xffffffff810df1e9 (__mcheck_cpu_cap_init+0x9/0x130) > Call Trace: > > mcheck_cpu_init+0x3d/0x2c0 > identify_cpu+0x85a/0x910 > identify_boot_cpu+0xc/0x98 > check_bugs+0x6/0xa7 > start_kernel+0x363/0x3d1 > secondary_startup_64_no_verify+0xe5/0xeb > > > It is annoying, but not fatal. The patchset is big enough as it is. > I tried to keep patch number under control. > I did hit panic as below. [ 0.578792] mce: MSR access error: RDMSR from 0x475 at rIP: 0xffffffffb94daa92 (mce_rdmsrl+0x22/0x60) [ 0.578792] Call Trace: [ 0.578792] [ 0.578792] machine_check_poll+0xf0/0x260 [ 0.578792] __mcheck_cpu_init_generic+0x3d/0xb0 [ 0.578792] mcheck_cpu_init+0x16b/0x4a0 [ 0.578792] identify_cpu+0x467/0x5c0 [ 0.578792] identify_boot_cpu+0x10/0x9a [ 0.578792] check_bugs+0x2a/0xa06 [ 0.578792] start_kernel+0x6bc/0x6f1 [ 0.578792] x86_64_start_reservations+0x24/0x26 [ 0.578792] x86_64_start_kernel+0xad/0xb2 [ 0.578792] secondary_startup_64_no_verify+0xe4/0xeb [ 0.578792] [ 0.578792] Kernel panic - not syncing: MCA architectural violation! [ 0.578792] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.17.0-rc5-td-guest-upstream+ #2 [ 0.578792] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 [ 0.578792] Call Trace: [ 0.578792] [ 0.578792] dump_stack_lvl+0x49/0x5f [ 0.578792] dump_stack+0x10/0x12 [ 0.578792] panic+0xf9/0x2d0 [ 0.578792] ex_handler_msr_mce+0x5e/0x5e [ 0.578792] fixup_exception+0x2f4/0x310 [ 0.578792] exc_virtualization_exception+0x9b/0x100 [ 0.578792] asm_exc_virtualization_exception+0x12/0x40 [ 0.578792] RIP: 0010:mce_rdmsrl+0x22/0x60 [ 0.578792] Code: a0 b9 e8 75 4d fb ff 90 55 48 89 e5 41 54 53 89 fb 48 c7 c7 9c c1 f6 b9 e8 4b 28 00 00 65 8a 05 97 52 b4 46 84 c0 75 10 89 d9 <0f> 32 48 c1 e2 20 48 09 d0 5b 41 5c 5d c3 89 df e8 c9 5a 17 ff 4c [ 0.578792] RSP: 0000:ffffffffba203cd8 EFLAGS: 00010246 [ 0.578792] RAX: 0000000000000000 RBX: 0000000000000475 RCX: 0000000000000475 [ 0.578792] RDX: 00000000000001d0 RSI: ffffffffb9f6c19c RDI: ffffffffb9ece016 [ 0.578792] RBP: ffffffffba203ce8 R08: ffffffffba203cb0 R09: ffffffffba203cb4 [ 0.578792] R10: 0000000000000000 R11: 000000000000000f R12: 0000000000000001 [ 0.578792] R13: ffffffffba203dc0 R14: 000000000000000a R15: 000000000000001d [ 0.578792] ? mce_rdmsrl+0x15/0x60 [ 0.578792] machine_check_poll+0xf0/0x260 [ 0.578792] __mcheck_cpu_init_generic+0x3d/0xb0 [ 0.578792] mcheck_cpu_init+0x16b/0x4a0 [ 0.578792] identify_cpu+0x467/0x5c0 [ 0.578792] identify_boot_cpu+0x10/0x9a [ 0.578792] check_bugs+0x2a/0xa06 [ 0.578792] start_kernel+0x6bc/0x6f1 [ 0.578792] x86_64_start_reservations+0x24/0x26 [ 0.578792] x86_64_start_kernel+0xad/0xb2 [ 0.578792] secondary_startup_64_no_verify+0xe4/0xeb [ 0.578792] [ 0.578792] ---[ end Kernel panic - not syncing: MCA architectural violation! ]---