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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 0D47CCA9EC7 for ; Wed, 30 Oct 2019 19:31:54 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 D312C20856 for ; Wed, 30 Oct 2019 19:31:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D312C20856 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id B4F7AE99; Wed, 30 Oct 2019 19:31:53 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id D0647E7B for ; Wed, 30 Oct 2019 19:31:52 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id F13BD174 for ; Wed, 30 Oct 2019 19:31:51 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 0CD73148; Wed, 30 Oct 2019 20:31:48 +0100 (CET) Date: Wed, 30 Oct 2019 20:31:48 +0100 From: Joerg Roedel To: Will Deacon Subject: Re: [PATCH 5/7] iommu/arm-smmu-v3: Allow building as a module Message-ID: <20191030193148.GA8432@8bytes.org> References: <20191030145112.19738-1-will@kernel.org> <20191030145112.19738-6-will@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191030145112.19738-6-will@kernel.org> User-Agent: Mutt/1.9.4 (2018-02-28) Cc: Bjorn Helgaas , iommu@lists.linux-foundation.org, Robin Murphy , linux-kernel@vger.kernel.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org Hi Will, On Wed, Oct 30, 2019 at 02:51:10PM +0000, Will Deacon wrote: > By removing the redundant call to 'pci_request_acs()' we can allow the > ARM SMMUv3 driver to be built as a module. > > Signed-off-by: Will Deacon > --- > drivers/iommu/Kconfig | 2 +- > drivers/iommu/arm-smmu-v3.c | 1 - > 2 files changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index e3842eabcfdd..7583d47fc4d5 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -388,7 +388,7 @@ config ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT > config. > > config ARM_SMMU_V3 > - bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support" > + tristate "ARM Ltd. System MMU Version 3 (SMMUv3) Support" > depends on ARM64 > select IOMMU_API > select IOMMU_IO_PGTABLE_LPAEa Sorry for the stupid question, but what prevents the iommu module from being unloaded when there are active users? There are no symbol dependencies to endpoint device drivers, because the interface is only exposed through the iommu-api, right? Is some sort of manual module reference counting needed? Joerg _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu