From nobody Sun Dec 14 02:31:40 2025 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (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 BE8581EB189 for ; Fri, 23 May 2025 00:23:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747959815; cv=none; b=N28zYYpfCCfqFXwQ/J4ylwxVeg7BpzcZdLZfAnw0Z0Ib+M23i7YpPJ7lMLEoOsoGd4j5bfHgQYbo3GPerqEglNRU+fRKTwTbr0s25Jhe7iTTBsysknNWq2kcjCxfzG6GVUu3XyaRlkGSzKqj1oAvF5vXIhL1L3tks39sKJzshYQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747959815; c=relaxed/simple; bh=ni6/WBCjdM2RubNKz7PsaUr5XBFthV8eQFmuWwqwsnA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=CRSuPpg8RPPL8vBkzn4e7g/6stVm00FSe0UEfsbAC+LCN62b0GsrZY0whYOddHIv9PvIAB8TGis2Q8ev7X7DlAgs8gW4sdO3uVZxA2mpgrx6RinGlxbqoV1xfYwrE+5tmsB6m4N+KFgYcLQMkVt6zxodzz7/fXbzueepjXqko4A= 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=KbwIBKAY; arc=none smtp.client-ip=192.198.163.8 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="KbwIBKAY" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1747959814; x=1779495814; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=ni6/WBCjdM2RubNKz7PsaUr5XBFthV8eQFmuWwqwsnA=; b=KbwIBKAYJQE0T4zTCIwAp6oQMvQm6siTtPHLY42rs1papxPDuHZ+XehI SvC+kjOkZGNSouzSoHBH5byWuWp7AvwLYcQ8PmY3zrp3sI2Je3jjv833I 0RdKBKk4DLLVVuxfZqDoEGNBTmjJgZbQkqd8FvDWqpA8GHfg4lY1C4HzQ k041N+RJ7rfJ+bozqpA/QRVmpMb5EjnQL57NHSECYtTFFesSixzoG6+xD veA9t0j+PzWxQOq/tfCCEeGBPa1RdFfYktCkuI0wBPAmJUNqSTgx0zHHW aXL80wx8P4YZc/11x7Id7361hxte2HHXH38KbkGTVJD176+K4GD/WbBEU Q==; X-CSE-ConnectionGUID: L5ueje4wTFerFX1gl7lxvA== X-CSE-MsgGUID: ApWCaHHWRzyHwENOxyRQWA== X-IronPort-AV: E=McAfee;i="6700,10204,11441"; a="67570561" X-IronPort-AV: E=Sophos;i="6.15,307,1739865600"; d="scan'208";a="67570561" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 May 2025 17:23:33 -0700 X-CSE-ConnectionGUID: i5JzeATaSPiTz7BG0vKbSQ== X-CSE-MsgGUID: soLVEmIvSPu5NF+ajCyZ/g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.15,307,1739865600"; d="scan'208";a="140665149" Received: from ww-dev.sh.intel.com ([10.239.48.95]) by orviesa009.jf.intel.com with ESMTP; 22 May 2025 17:23:31 -0700 From: Wei Wang To: baolu.lu@linux.intel.com, kevin.tian@intel.com, yi.l.liu@intel.com, dwmw2@infradead.org, jroedel@suse.de, linux-kernel@vger.kernel.org, iommu@lists.linux.dev Cc: Wei Wang Subject: [PATCH v1] iommu/vt-d: Remove the redundant logic in first_level_by_default() Date: Fri, 23 May 2025 16:10:56 +0800 Message-ID: <20250523081056.223082-1-wei.w.wang@intel.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This original implementation included redundant logic to determine whether first-stage translation should be used by default. Simplify it and preserve the original behavior: - Returns false in legacy mode (no scalable mode support). - Defaults to first-level translation when both FLTS and SLTS are supported. Signed-off-by: Wei Wang Reviewed-by: Kevin Tian --- drivers/iommu/intel/iommu.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index cb0b993bebb4..228da47ab7cd 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -1366,15 +1366,7 @@ static void free_dmar_iommu(struct intel_iommu *iomm= u) */ static bool first_level_by_default(struct intel_iommu *iommu) { - /* Only SL is available in legacy mode */ - if (!sm_supported(iommu)) - return false; - - /* Only level (either FL or SL) is available, just use it */ - if (ecap_flts(iommu->ecap) ^ ecap_slts(iommu->ecap)) - return ecap_flts(iommu->ecap); - - return true; + return sm_supported(iommu) && ecap_flts(iommu->ecap); } =20 int domain_attach_iommu(struct dmar_domain *domain, struct intel_iommu *io= mmu) --=20 2.43.0