From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) (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 569D221ABC1 for ; Mon, 19 Jan 2026 19:50:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768852250; cv=none; b=IG+7HHH9j+skvy0LHNdITCN17p+I9B8If+6dNwZ8abxL2mWHl6BugC6RPaMBum74BvHYvqrBuiezKM7WvM9heA6ZWKHlpAjoY9ULed3ai7oEStT3zzM0qq5Uyd0jslQvtbkplM7Z+htwghfW9WyBWL0qbo4409VHMjjWW/pdCkc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768852250; c=relaxed/simple; bh=jELnnzK/fY8sX5I9ukyhDfCzo/m2KM8kFmEkdc21VnA=; h=Subject:To:Cc:From:Date:Message-Id; b=tD6bK6OcU3yLyMFs3peXuyYne55taWQw25BmJEu0cl/KR3SnFfJn4j7xEMYac2u0ejwS/rX102hlgkPWp72g9dNlJpK2oyq3lgJQbCWOjIxlfS0gS2ek9h1tOkj/FCw3Afby5zBvAkaxQ51Gwn78AZU/HcLtBLtmbrLXkU5iMGk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=miyTQ2VC; arc=none smtp.client-ip=192.198.163.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="miyTQ2VC" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1768852249; x=1800388249; h=subject:to:cc:from:date:message-id; bh=jELnnzK/fY8sX5I9ukyhDfCzo/m2KM8kFmEkdc21VnA=; b=miyTQ2VCNYTlYxUgPhgelzCdslq/w/kYOkMRwx3apoJrzous/XqDHGQY x9lLqzcuylGMR3eLiS6346bYpknfViGoloa3NzapfQXDr7qIDBHf5UNP5 70oqgfL+rK59IFG6HMl5DGehac7l0XBIjWB91VDqDIjHxpDZspVgTfPij yD8YAO3h4ptZ/unPmqAnkuLP1yV03SLcDnqLlqx0LCE+hDWEHXkZMCCIm zDHP6Zn/vK6Dw5z30b3ZBdtSSTgnnPUqCxFIcx+QtZgZud1da1Lk/vnne Y8meiXpVAdSp2hjXKS0cwQSI9qs2GcWAfz7wsgWq3/tKKrDSUusNEXLWM A==; X-CSE-ConnectionGUID: kcBJwEdgR6WRMGRpQhIN3g== X-CSE-MsgGUID: ZzRR3q0LT+GQZbjU0Aj6kQ== X-IronPort-AV: E=McAfee;i="6800,10657,11676"; a="57623047" X-IronPort-AV: E=Sophos;i="6.21,238,1763452800"; d="scan'208";a="57623047" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jan 2026 11:50:48 -0800 X-CSE-ConnectionGUID: 7X+hfbTHTou05vaHuAuABA== X-CSE-MsgGUID: nh21o/GFRV6sRHxcxCxQSw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,238,1763452800"; d="scan'208";a="210786554" Received: from davehans-spike.ostc.intel.com (HELO localhost.localdomain) ([10.165.164.11]) by fmviesa004.fm.intel.com with ESMTP; 19 Jan 2026 11:50:48 -0800 Subject: [PATCH 0/6] x86/cpu: Take Intel platform into account for old microcode checks To: linux-kernel@vger.kernel.org Cc: sohil.mehta@intel.com, Dave Hansen , Borislav Petkov , "H. Peter Anvin" , Ingo Molnar , Jon Kohler , Pawan Gupta , "Peter Zijlstra (Intel)" , Thomas Gleixner , Tony Luck , x86@kernel.org From: Dave Hansen Date: Mon, 19 Jan 2026 11:50:47 -0800 Message-Id: <20260119195047.86E3C696@davehans-spike.ostc.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: There was a report[1] that CPUs running updated microcode were being reported as running old microcode. The reason is that the old microcode list neglects to take the platform ID into account. The platform ID is an Intel-only construct that allows CPUs that otherwise have the same model/family/stepping to take different microcode revisions. The microcode loader itself already checks this. Only the recent "old_microcode" checker failed here. Treat the platform ID as a peer of model/family/stepping. Store it in 'struct cpuinfo_x86', enable matching on it with with 'struct x86_cpu_id', and flesh out the 'old_microcode' list with it. This fixes the report of an inaccurate, false positive in the 'old_microcode' vulnerability file. 1. https://lore.kernel.org/all/38660F8F-499E-48CD-B58B-4822228A5941@nutanix.com/ Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: Tony Luck Cc: Pawan Gupta Cc: "Peter Zijlstra (Intel)" Cc: x86@kernel.org Cc: Jon Kohler