From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 49BABC77B61 for ; Fri, 28 Apr 2023 15:52:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345989AbjD1Pwa (ORCPT ); Fri, 28 Apr 2023 11:52:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229843AbjD1Pw2 (ORCPT ); Fri, 28 Apr 2023 11:52:28 -0400 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6535B4212; Fri, 28 Apr 2023 08:52:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1682697147; x=1714233147; h=date:from:to:cc:subject:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0VSoxdyPY93P2BuKRz02q7jUM3wZLua7CfSmMyaDnso=; b=NVULFCiFLXzYaJGPiMN9AeHl67w4PShs1P7rCRtR21Myn8LnRslarZwF Ebyd1GFFXze066IHy03ueUVFaBOvoSMlathxTUuoorDVIVqEwZDDUSKlB SAXBvxO5VdF/jBQt3O61pV302XHfTyPMK2AmwLI9ZEL0QJZgn74mStjim E7zzHtrdlZ2mqRBld4aANDDL1lmgzcIttzhY23XraXrbeRQSGtH7fAD/I SrA5dZef7SjJZU7CKtLBPWML/zfRnBN6CS92WXxx9Y24yPP0skA/Nk+Fv 37TBkBHprzsOqjMpm2gVVJ4AQNgg3WsMgm6TS+my2+OTa0DMEH5z+Omva w==; X-IronPort-AV: E=McAfee;i="6600,9927,10694"; a="332100069" X-IronPort-AV: E=Sophos;i="5.99,235,1677571200"; d="scan'208";a="332100069" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2023 08:52:26 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10694"; a="645184066" X-IronPort-AV: E=Sophos;i="5.99,234,1677571200"; d="scan'208";a="645184066" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.24.100.114]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2023 08:52:26 -0700 Date: Fri, 28 Apr 2023 08:56:45 -0700 From: Jacob Pan To: "Tian, Kevin" Cc: LKML , "iommu@lists.linux.dev" , Robin Murphy , Jason Gunthorpe , Lu Baolu , Joerg Roedel , "dmaengine@vger.kernel.org" , "vkoul@kernel.org" , Will Deacon , David Woodhouse , "Raj, Ashok" , "Liu, Yi L" , "Yu, Fenghua" , "Jiang, Dave" , "Luck, Tony" , "Zanussi, Tom" , "Ranganathan, Narayan" , jacob.jun.pan@linux.intel.com Subject: Re: [PATCH v5 2/7] iommu/sva: Explicitly exclude RID_PASID from SVA Message-ID: <20230428085645.0310c4ca@jacob-builder> In-Reply-To: References: <20230427174937.471668-1-jacob.jun.pan@linux.intel.com> <20230427174937.471668-3-jacob.jun.pan@linux.intel.com> Organization: OTC X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Hi Kevin, On Fri, 28 Apr 2023 09:40:12 +0000, "Tian, Kevin" wrote: > > From: Jacob Pan > > Sent: Friday, April 28, 2023 1:50 AM > > > > SVA PASID allocation is hardcoded to start from 1 because 0 is used for > > RID_PASID, let's make it explicit to avoid the potential conflicts. > > > > Signed-off-by: Jacob Pan > > --- > > drivers/iommu/iommu-sva.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c > > index c434b95dc8eb..ac7c93bacb5c 100644 > > --- a/drivers/iommu/iommu-sva.c > > +++ b/drivers/iommu/iommu-sva.c > > @@ -66,7 +66,7 @@ struct iommu_sva *iommu_sva_bind_device(struct > > device *dev, struct mm_struct *mm > > return ERR_PTR(-EOPNOTSUPP); > > > > /* Allocate mm->pasid if necessary. */ > > - ret = iommu_sva_alloc_pasid(mm, 1, max_pasids - 1); > > + ret = iommu_sva_alloc_pasid(mm, IOMMU_DEF_RID_PASID + 1, > > max_pasids - 1); > > To be future proof it's probably cleaner to define a > IOMMU_MAX_RSVD_PASID in case there may be more reserved > pasids in future usages? much better, will do. Thanks, Jacob