From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (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 74B023603D7 for ; Sat, 29 Aug 2026 06:08:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787983684; cv=none; b=M0On3wzNJh86PgXrXfvc1mxHWNKa25HNzKLRtnvu5I8S37a8QTnUbDTwCL3KDzmSlJMvKQeDrk0I+EEAU2rfG6kKaHoFvJgMNjdEzyfMCHtRcGAqlONhfpPv6wFSKLx8sKUwh87IU+g632o7fQVMcNGAhQcBtMbxCwzoWBoWFE8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787983684; c=relaxed/simple; bh=BRp3sUhJq7vcMcoUSMNTEQQai41QCEr1vyAeOR4UNsk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=YEqPEg+L8CSm3JpKdhAoqUsL1BzA5Toqp0S5xZhthc0FMXMmmI80paI5L/tYR631uyXHl0a9ffVaEamuL89C/GNHuXOC6ELejmG1/Td12qI1ubEL6TOeY0M/Qs5QIUFNLS5sZ8AucuB2Jk8I4Ers2xa6gsPhB1wG+FkBYYdCb6k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=a1JlD6zP; arc=none smtp.client-ip=198.175.65.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="a1JlD6zP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1787983683; x=1819519683; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=BRp3sUhJq7vcMcoUSMNTEQQai41QCEr1vyAeOR4UNsk=; b=a1JlD6zPL01+ONq8+YhQ4Cvpl+ZTGCmt7GfvOSZNDmDaCbKQy2m0oppP MKuS0/gtli3bX/1iTFiZNjBp5WbA41t+nPOEAmrws12tg3JhS14HmYgv+ sefYgXc7XKMdUZsI12ocb6FZTOPIcYkcxNOep6IgFy8p5HxlvnXh5C468 6KbdTSCG9xHHI5Mk6FzaTw0nWFRMARx0PgNd0VcOyj1gpTXTdk0hmokTu IwituiR8LbXuFGerXMBCEz9euwSY6GWo7FraWfHptPrrkLHEIJNoq1in2 k2V2oUe33UhOExeU03O4Kt8ts6lBMF39KmUVCKKvzORzowSzS+ITgwBi6 A==; X-CSE-ConnectionGUID: JJtJGyACQNuYF354VLnaLw== X-CSE-MsgGUID: MAYRKI+iQeeipdoIs2t9CA== X-IronPort-AV: E=McAfee;i="6800,10657,11889"; a="88685896" X-IronPort-AV: E=Sophos;i="6.25,250,1779174000"; d="scan'208";a="88685896" Received: from orviesa006.jf.intel.com ([10.64.159.146]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Aug 2026 23:08:03 -0700 X-CSE-ConnectionGUID: Kb/5FxWFRHu1S+YHf/2DfA== X-CSE-MsgGUID: e/pEZ35tQKeBgiI3n5F34Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,250,1779174000"; d="scan'208";a="266543551" Received: from chenyu-dev.sh.intel.com ([10.239.62.107]) by orviesa006.jf.intel.com with ESMTP; 28 Aug 2026 23:07:59 -0700 From: Chen Yu To: tony.luck@intel.com, reinette.chatre@intel.com Cc: tglx@kernel.org, bp@alien8.de, mingo@redhat.com, dave.hansen@linux.intel.com, hpa@zytor.com, fenghuay@nvidia.com, babu.moger@amd.com, chen.yu@linux.dev, x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 2/9] x86/resctrl: Require 64-bit x86 for resctrl support Date: Sat, 29 Aug 2026 13:57:33 +0800 Message-Id: <185a82864956b6c029fc7fd9525f68dbae1d1fc1.1787976868.git.yu.c.chen@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit All known hardware that supports Intel RDT or AMD QoS is 64-bit. MMIO-based Enhanced RDT (ERDT) monitoring requires readq()/writeq(), which are only available on 64-bit. 32-bit x86 is maintained for legacy reasons. New CPU features are generally not enabled for 32-bit systems, its test coverage keeps shrinking, and modern 32-bit distributions have become rare. Discouraging the use of a 32-bit kernel is discussed at: https://lore.kernel.org/all/c6ab0c24-8931-4f0d-9be6-23498ab4c38b@intel.com/ Drop 32-bit support by changing the X86_CPU_RESCTRL dependency from X86 to X86_64. Since X86_CPU_RESCTRL now implies X86_64, remove the redundant X86_64 dependency from X86_CPU_RESCTRL_INTEL_AET. Signed-off-by: Chen Yu Tested-by: Hongyu Ning --- v6->v7: Replace the inaccurate "no realistic server use case" rationale with the legacy, shrinking test coverage and rare distro reasoning. (Reinette Chatre, Tony Luck, Dave Hansen, Borislav Petkov, Peter Zijlstra) --- arch/x86/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index bdad90f210e4..6685e120cff3 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -514,7 +514,7 @@ config X86_MPPARSE config X86_CPU_RESCTRL bool "x86 CPU resource control support" - depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD) + depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD) depends on MISC_FILESYSTEMS select ARCH_HAS_CPU_RESCTRL select RESCTRL_FS @@ -537,7 +537,7 @@ config X86_CPU_RESCTRL config X86_CPU_RESCTRL_INTEL_AET bool "Intel Application Energy Telemetry" - depends on X86_64 && X86_CPU_RESCTRL && CPU_SUP_INTEL && INTEL_PMT_TELEMETRY=y && INTEL_TPMI=y + depends on X86_CPU_RESCTRL && CPU_SUP_INTEL && INTEL_PMT_TELEMETRY=y && INTEL_TPMI=y help Enable per-RMID telemetry events in resctrl. -- 2.25.1