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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A8ADC433E0 for ; Tue, 26 Jan 2021 22:25:09 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DBF2A20665 for ; Tue, 26 Jan 2021 22:25:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DBF2A20665 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=yFqnigOY3p2KzXI13GGKVHVRygt3Uy59TRgYCDrNeuw=; b=GqJEnh/uiRXn/Ml+a0/RzuIID clKwu9SkHaK/hWjEdGgjmPXHJ8VGM2Y2H/+fj2KV6CsNrWSA6LdAYBTIVcOyPx6syP106TUn9HCTl v5sol7c5Hlio5AzSV2n6bvWK5imqyMdnNET30+1kY8XwzztI7uFyfR+hU8ktAcGnSCP+P7uoEvTge E4W16UCo4Cq3onpYjbJrBCSpQE5+Wv4Rc32bdQQXH62KLJo5ZlFTHhUgmnGdNUBmoeN3nxmzVO63y RxTjgP0VMu4IWDoe/aXAa5BDhMjzOsDu/LfqN9AsYDF1m+XWQKg73Zn3yJ3nxOLITVj174omqJWl6 q/ZqeBpNg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4Wk0-0004MM-PR; Tue, 26 Jan 2021 22:23:16 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4Wjx-0004Lu-VX; Tue, 26 Jan 2021 22:23:14 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id D75302065D; Tue, 26 Jan 2021 22:23:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1611699792; bh=fdRIENxKcgc5beyovt2puqoCoi+rEtNpR+KyZhmJt9I=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=achoEHu8k4uN8E83dNG429NPT1uvW4BKjuDha0qFlXbMfhUNqyWIOkGFmn5FIYQjx AAQs2T+cmT/3KagO8qWzYc02+OPzJ8Y0qoV6PONAnxAgS75ryj9A2u9zfPw9P6NK8M cHG5i9P/T7hfT5C7tU+Gu5rsDwAD1jYs0hcLmgrgWzCKcc2j5HXL5Tr/whN3VyMMdQ bx4w3RT7i0ULUk3PrLkCR1ZpN3A9ZiqNQD7ru816XaXg4IngNyw1pIqGVHsHxZ/upn BHC4hf5TqThjyZuxdwR0BPmGGFv4S+W11JMY00+TYtCZw7qigBK4Q9XevrSXLk7/eK peDrVc1pqOHww== Date: Tue, 26 Jan 2021 22:23:06 +0000 From: Will Deacon To: Yong Wu Subject: Re: [PATCH v6 07/33] iommu: Avoid reallocate default domain for a group Message-ID: <20210126222305.GB30460@willie-the-truck> References: <20210111111914.22211-1-yong.wu@mediatek.com> <20210111111914.22211-8-yong.wu@mediatek.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210111111914.22211-8-yong.wu@mediatek.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210126_172314_102763_949B5513 X-CRM114-Status: GOOD ( 17.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: youlin.pei@mediatek.com, devicetree@vger.kernel.org, Nicolas Boichat , srv_heupstream@mediatek.com, chao.hao@mediatek.com, Joerg Roedel , linux-kernel@vger.kernel.org, Evan Green , Tomasz Figa , iommu@lists.linux-foundation.org, Rob Herring , linux-mediatek@lists.infradead.org, Krzysztof Kozlowski , Matthias Brugger , anan.sun@mediatek.com, Robin Murphy , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jan 11, 2021 at 07:18:48PM +0800, Yong Wu wrote: > If group->default_domain exists, avoid reallocate it. > > In some iommu drivers, there may be several devices share a group. Avoid > realloc the default domain for this case. > > Signed-off-by: Yong Wu > --- > drivers/iommu/iommu.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 3d099a31ddca..f4b87e6abe80 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -266,7 +266,8 @@ int iommu_probe_device(struct device *dev) > * support default domains, so the return value is not yet > * checked. > */ > - iommu_alloc_default_domain(group, dev); > + if (!group->default_domain) > + iommu_alloc_default_domain(group, dev); I don't really get what this achieves, since iommu_alloc_default_domain() looks like this: static int iommu_alloc_default_domain(struct iommu_group *group, struct device *dev) { unsigned int type; if (group->default_domain) return 0; ... in which case, it should be fine? Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel