From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-24416.protonmail.ch (mail-24416.protonmail.ch [109.224.244.16]) (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 5B52743D50E for ; Tue, 20 Jan 2026 14:34:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=109.224.244.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768919688; cv=none; b=JXjbFY+DM0MbUWyQVroiMsdfqNV1YRHb38XvVfFAJkK9B4tLyphUzHkFX+i3Vv1O4iw9PN3Vhcef1PDvMXj6vEY+F6OUWSx8Rv7BTtutd30gz2SsD/6t5aVs4A82qNb5gyWHY3qVZQkaOcutKEZBB/fcNB3/v3qvgV3WXqvOvGU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768919688; c=relaxed/simple; bh=2Wl9OPmdshrwWppcrsRIBd8MR5jj04mWr/F4GHb1v1E=; h=Date:To:From:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=L2zjiy6qJL7wfAfb6AloC9Dd5U4YXtM1f+p3tsyHF9X60YxE6eWhz5mwI5/7I1UyAPdVEKnTfnkdSYMCLrq8M7kaEv+1wIN5hnQi3yWioNA+JM0pDgHx1fQgHPAA7h1GJvl1Ca17wdZ6Kg854Sg46wO+4Rmg90ZPHbuOZkUv2KQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me; spf=pass smtp.mailfrom=pm.me; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b=qfR3NPS1; arc=none smtp.client-ip=109.224.244.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pm.me Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b="qfR3NPS1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pm.me; s=protonmail3; t=1768919676; x=1769178876; bh=lgHzrEmc6Twr86d3/d6sFi+bWmKTV44O6xxL+P9XnoY=; h=Date:To:From:Cc:Subject:Message-ID:Feedback-ID:From:To:Cc:Date: Subject:Reply-To:Feedback-ID:Message-ID:BIMI-Selector; b=qfR3NPS11l1GjvMlc12QH8K6mYLlyktdYMQUGm8MmdmHzYSDhqNd2KADUBWhU7wyZ FBEdkVoghkDtH8F67hzqRELRqXibEfmRfZOUeFzXAHvsqmyDb1WchAJeGpnrU/lGfj NI5yw6fnjDS76EGp/KnrBpltOsmyQTAIIyGD7ogd1V0XtV7emhorR/+5K0A0rfuW3o 1kM48q+nAc2KbHNxTTTK/bq25i36xpot1nhX1zFVeiudJM+iHxZwbCE1htcL0pqej3 PGREc/smxpfMFJUvV5gnCYovUmONewAa5RbwbagXgrR8DachI0lkO1vPq4ZJD19yGL mJ8nvuceYMtnw== Date: Tue, 20 Jan 2026 14:34:30 +0000 To: Dave Hansen From: Maciej Wieczor-Retman Cc: linux-kernel@vger.kernel.org, sohil.mehta@intel.com, Borislav Petkov , "H. Peter Anvin" , Ingo Molnar , Jon Kohler , Pawan Gupta , "Peter Zijlstra (Intel)" , Thomas Gleixner , Tony Luck , x86@kernel.org Subject: Re: [PATCH 4/6] x86/cpu: Add platform ID to CPU info structure Message-ID: Feedback-ID: 164464600:user:proton X-Pm-Message-ID: 8ec54f66c20e6adeefd9331a5254bcc3b45fd509 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 2026-01-19 at 11:50:55 -0800, Dave Hansen wrote: > >From: Dave Hansen > >The end goal here is to be able to do x86_match_cpu() and match on a >specific platform ID. While it would be possible to stash this ID >off somewhere or read it dynamically, that approaches would not be >consistent with the other fields which can be matched. > >Read the platform ID and store it in cpuinfo_x86->x86_platform_id. > >There are lots of sites to set this new field. Place it near >the place c->microcode is established since the platform ID is >so closely intertwined with microcode updates. > >Note: This should not grow the size of 'struct cpuinfo_x86' in >practice since the u8 fits next to another u8 in the structure. > >Signed-off-by: Dave Hansen >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 >--- > > b/arch/x86/include/asm/processor.h | 1 + > b/arch/x86/kernel/cpu/common.c | 4 +++- > b/arch/x86/kernel/cpu/intel.c | 1 + > 3 files changed, 5 insertions(+), 1 deletion(-) > >diff -puN arch/x86/include/asm/processor.h~cpu-x86_stepping arch/x86/inclu= de/asm/processor.h >--- a/arch/x86/include/asm/processor.h~cpu-x86_stepping=092026-01-19 11:38= :09.341914025 -0800 >+++ b/arch/x86/include/asm/processor.h=092026-01-19 11:38:09.444917962 -08= 00 >@@ -140,6 +140,7 @@ struct cpuinfo_x86 { > =09=09__u32=09=09x86_vfm; > =09}; > =09__u8=09=09=09x86_stepping; >+=09__u8=09=09=09x86_platform_id; /* Intel-only. 3 bits */ Should platform ID be added to print_cpu_info()? So it's printed alongside (family: 0xN model: 0xN, stepping: 0xN) --=20 Kind regards Maciej Wiecz=C3=B3r-Retman