From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx2.zhaoxin.com (mx2.zhaoxin.com [61.152.208.219]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8B4A82741DF for ; Thu, 12 Mar 2026 02:19:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=61.152.208.219 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773281955; cv=none; b=AneNFh9asnRypYe5fczVzc6UKeI4IvA2OpBHIqqrtAZiMHE4GxjogM4Ut/JG3W9MhlZNDlKBI5ZNDyGxB5WuaFmEdsM9Y9QrboI8FqA8ldgTMo7ivOeokSv0H37sZXWC34vlyQtuwrFocESWzE7t+nFBdoGUVzDno3DCrFNje/M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773281955; c=relaxed/simple; bh=y+40TWpBQ2zOxGY+nsk1kvKXHJo/yz5hLRfwRDOlt7g=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=oKv4I4cv+FCxbKGMAJTtIbkcDTmSrDSMe+1DjlE4HPGJ3Lh7yyj+nWCZXPLJOhJwdMm6YGVFg4uhzGuDfbdIGILS7yoJaWEANNwFZADj3hoEm1AWtIxoDkDm2rVd3Ro3MM2AGyLYLwJekQThDYbdaHAVHNefOpqMjTi5AOw+AXI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=zhaoxin.com; spf=pass smtp.mailfrom=zhaoxin.com; arc=none smtp.client-ip=61.152.208.219 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=zhaoxin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zhaoxin.com X-ASG-Debug-ID: 1773281949-1eb14e06ec0c440001-xx1T2L Received: from zhaoxin.com (zxmail.zhaoxin.com [10.28.208.166]) by mx2.zhaoxin.com with ESMTP id Ao9zuXIpI4CvRof1; Thu, 12 Mar 2026 10:19:09 +0800 (CST) X-Barracuda-Envelope-From: TonyWWang-oc@zhaoxin.com X-Barracuda-RBL-Trusted-Forwarder: 10.28.208.166 Received: from [10.32.64.22] ([10.32.64.22] [10.32.64.22]) by zhaoxin.com (f222c4) with ESMTP5ec05cd12c134825a730b52d4c57502c Thu, 12 Mar 2026 10:19:04 +0800 X-Eyou-Smtpauth: tonywwangoc@zhaoxin.com X-Barracuda-RBL-Trusted-Forwarder: 10.32.64.22 X-Eyou-EnvelopeSender: TonyWWang-oc@zhaoxin.com Message-ID: <8176878c-970a-48e3-b237-2c57ed39f7a5@zhaoxin.com> Date: Thu, 12 Mar 2026 10:18:38 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] x86/cpu/centaur: Disable X86_FEATURE_FSGSBASE on Zhaoxin C4600 To: ludloff@gmail.com X-ASG-Orig-Subj: Re: [PATCH] x86/cpu/centaur: Disable X86_FEATURE_FSGSBASE on Zhaoxin C4600 Cc: me@ziyao.cc, andrew.cooper3@citrix.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, stable@vger.kernel.org, tglx@kernel.org, x86@kernel.org, lukelin@viacpu.com, "TimGuo@zhaoxin.com" , cooperyan@zhaoxin.com, benjaminpan@viatech.com, QiyuanWang@zhaoxin.com, HerryYang@zhaoxin.com, "CobeChen@zhaoxin.com" References: Content-Language: en-US From: Tony W Wang-oc In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Eyou-Sender: X-Vid: 0bc6c7cd8a2ebb3ddea73d59766eff8f00@zhaoxin.com X-Barracuda-Connect: zxmail.zhaoxin.com[10.28.208.166] X-Barracuda-Start-Time: 1773281949 X-Barracuda-URL: https://10.28.252.36:4443/cgi-mod/mark.cgi X-Virus-Scanned: by bsmtpd at zhaoxin.com X-Barracuda-Scan-Msg-Size: 1541 X-Barracuda-BRTS-Status: 1 X-Barracuda-Bayes: INNOCENT GLOBAL 0.0000 1.0000 -2.0210 X-Barracuda-Spam-Score: -2.02 X-Barracuda-Spam-Status: No, SCORE=-2.02 using global scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=1000.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.3.155726 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- On 2026/3/6 04:26, Christian Ludloff wrote: > > > Tony, > > can you confirm whether F=6 M=1F is affected or not? > (Supposedly that's ZX-D... but the F in the model does > make me wonder/ask.) > This bug existed only in certain early ucode revisions of the ZX-C/ZX-C+ series CPUs, and is not present in the ZX-D. > Presumably the 6FE and 10690 microcodes which are > out in the wild do not fix the bug, correct? > > 000006fe_00000000_20110809_8f396f73 > 000006fe_00000000_20110809_8f397072 > 000006fe_00000001_20160525_7214d1e1 > 000006fe_00000001_20170109_25646399 > 000006fe_00000001_20180726_6e07329b > 000006fe_00000001_20180726_6e1e984b > > 00010690_00000000_20110809_259878a5 > 00010690_00000001_20160525_3c34fc1a > 00010690_00000001_20170109_a8b24dc2 > 00010690_00000001_20180726_0c55f25d > 00010690_00000001_20180726_41faefde > No, The four patches with the display date of 20180726 should not have this bug. > As for making the code conditional for Centaur/Zhaoxin, > stepping E seems to be when FSGSBASE arrived – and > while there are CPUID dumps for 6FE that say VIA Eden > it is possible that they too have the bug. > Sorry, VIA Eden is too old, we haven't been able to find actual hardware to confirm this. > As for making the code conditional for Zhaoxin models in > the string, that would require more than just C4600 – the > collection of known dumps includes others. > Yes, ZX-C/ZX-C+ series CPUs have other strings. Sincerely! TonyWWang-oc > -- > C.